Help is provided for the system parameters listed below.
1 – ACP_BASEPRIO
ACP_BASEPRIO sets the base priority for all ACPs. The DCL command
SET PROCESS/PRIORITY can be used to reset the base priorities of
individual ACPs. ACP_BASEPRIO is not applicable for XQPs.
ACP_BASEPRIO is a DYNAMIC parameter.
2 – ACP_DATACHECK
ACP_DATACHECK controls the consistency checks that are performed
on internal file system metadata such as file headers.
ACP_DATACHECK is a bit mask. The following table shows the bits
that are defined currently:
Bit Description
0 Set this bit to perform consistency checks on read
operations.
When this bit is set, the IO$M_DATACHECK function
modifier is automatically set on all subsequent IO$_
READLBLK operations that read file system metadata (see
the OpenVMS I/O User's Reference Manual).
1 Set this bit to perform consistency checks on write
operations.
When this bit is set, the IO$M_DATACHECK function
modifier is automatically set on all subsequent IO$_
WRITELBLK operations that read file system metadata
(see the OpenVMS I/O User's Reference Manual).
2 Set this bit to perform read-after-write consistency
checks.
This is similar to setting bit 1, except that in this
case the file system does the checks, not the lower
level device or disk driver.
Note that read-after-write consistency checks are not
allowed on deferred writes. Deferred writes are turned
off if this bit is set.
3 reserved for VSI use only; must be zero.
4 reserved for VSI use only; must be zero.
5 and 6 These two bits control the checks that are performed on
reads and writes of directory blocks. You can select
one of four different levels:
By
Select Setting
This Bit 6 And Bit 5
To Check That... Level... to... to...
The block is a valid 0 0 0
directory block
(reads only)
The block is a valid 1 0 1
directory block
(reads and writes)
The block is a valid 2 1 0
directory block
and contains valid
entries (reads and
writes)
The block is a valid 3 1 1
directory block
and contains valid
entries in correct
alphanumeric order
(reads and writes)
When you set the SYSTEM_CHECK system parameter to 1,
you enable level 3 checking of directory blocks.
Write errors result in BUGCHECK and crash your system;
read errors exit with error status SS$_BADDIRECTORY.
7 reserved for VSI use only; must be zero.
3 – ACP_DINDXCACHE
ACP_DINDXCACHE controls the size of the directory index cache
and the number of buffers used on a cachewide basis. Also,
ACP_DINDXCACHE builds a temporary index into the directory
file, thereby reducing search time and directory header lookup
operations.
ACP_DINDXCACHE is an AUTOGEN, DYNAMIC, and FEEDBACK parameter.
4 – ACP_DIRCACHE
ACP_DIRCACHE sets the number of pages for caching directory
blocks. Too small a value causes excessive XQP I/O operations,
while too large a value causes excessive physical memory to be
consumed by the directory data block cache.
ACP_DIRCACHE is an AUTOGEN, DYNAMIC, and FEEDBACK parameter.
5 – ACP_EXTCACHE
ACP_EXTCACHE sets the number of entries in the extent cache.
Each entry points to one contiguous area of free space on disk.
A specification of 0 means no cache. Too small a value causes
excessive XQP I/O operations, while too large a value causes
excessive physical memory to be consumed by the extent cache.
ACP_EXTCACHE is a DYNAMIC and FEEDBACK parameter.
6 – ACP_EXTLIMIT
ACP_EXTLIMIT specifies the maximum amount of free space to
which the extent cache can point, expressed in thousandths of
the currently available free blocks on the disk. For example,
if available free space on the disk is 20,000 blocks, a
specification of 10 limits the extent cache to 200 blocks.
The computed, installed value is usually adequate. Users with
four or more OpenVMS Cluster node systems might want to adjust
this parameter.
ACP_EXTLIMIT is a DYNAMIC parameter.
7 – ACP_FIDCACHE
ACP_FIDCACHE sets the number of file identification slots cached.
A specification of 1 means no cache. Too small a value causes
excessive XQP I/O operations, while too large a value causes
excessive physical memory to be consumed by the FID caches.
ACP_FIDCACHE is a DYNAMIC and FEEDBACK parameter.
8 – ACP_HDRCACHE
ACP_HDRCACHE sets the number of pages for caching file header
blocks. Too small a value causes excessive XQP I/O operations,
while too large a value causes excessive physical memory to be
consumed by the file header caches.
ACP_HDRCACHE is an AUTOGEN, DYNAMIC, and FEEDBACK parameter.
9 – ACP_MAPCACHE
ACP_MAPCACHE sets the number of pages for caching index file
bitmap blocks. Too small a value causes excessive XQP I/O
operations, while too large a value causes excessive physical
memory to be consumed by the bitmap cache.
ACP_MAPCACHE is an AUTOGEN, DYNAMIC, and FEEDBACK parameter.
10 – ACP_MAXREAD
ACP_MAXREAD sets the maximum number of directory blocks read in
one I/O operation.
ACP_MAXREAD is a DYNAMIC parameter.
11 – ACP_MULTIPLE
ACP_MULTIPLE enables (1) or disables (0) the default creation of
a separate disk XQP cache for each volume mounted on a different
device type. Prior to Version 4.0, a separate ACP process was
created for each device type if this parameter was enabled.
Because ACP operations are now handled by the per process XQP,
such separate processes are no longer created. In general, having
multiple caches is unnecessary. One large cache is more efficient
than several small ones. ACP_MULTIPLE can be overridden on an
individual-volume basis with the DCL command MOUNT.
ACP_MULTIPLE is an AUTOGEN and DYNAMIC parameter.
12 – ACP_QUOCACHE
ACP_QUOCACHE sets the number of quota file entries cached. A
specification of 0 means no cache. Too small a value causes
excessive XQP I/O operations, while too large a value causes
excessive physical memory to be consumed by the quota caches.
ACP_QUOCACHE is an AUTOGEN, DYNAMIC, and FEEDBACK parameter.
13 – ACP_REBLDSYSD
ACP_REBLDSYSD specifies whether the system disk should be rebuilt
if it was improperly dismounted with extent caching, file number
caching, or disk quota caching enabled. The ACP_REBLDSYSD default
value (1) ensures that the system disk is rebuilt. Setting the
value to 0 means the disk is not rebuilt.
Depending on the amount of caching enabled on the volume
before it was dismounted, the rebuild operation may consume a
considerable amount of time. Setting the value of ACP_REBLDSYSD
to 0 specifies that the disk should be returned to active service
immediately. If you set ACP_REBLDSYSD to 0, you can enter the DCL
command SET VOLUME/REBUILD at any time to rebuild the disk.
14 – ACP_SHARE
ACP_SHARE enables (0) or disables (1) the creation of a global
section for the first ACP used, enabling succeeding ACPs to share
its code. This parameter should be set to 0 when ACP_MULTIPLE is
on.
ACP_SHARE is a DYNAMIC parameter.
15 – ACP_SWAPFLGS
ACP_SWAPFLGS enables or disables swap through the value of a
4-bit number for the following four classes of ACPs:
Bit Class of ACP
0 Disks mounted by MOUNT/SYSTEM
1 Disks mounted by MOUNT/GROUP
2 Private disks
3 Magnetic tape ACP
If the value of the bit is 1, the corresponding class of ACPs
can be swapped. The value of decimal 15 (hexadecimal F-all bits
on) enables swap for all classes of ACP. A value of decimal
14 disables swap for ACPs for volumes mounted with the /SYSTEM
qualifier but leaves swap enabled for all other ACPs. Note that
one has only disk ACPs present if they are specifically requested
at mount time or if a Files-11 On-Disk Structure Level 1 disk is
mounted. In general, only bit 3 is significant because usually no
file ACPs exist.
ACP_SWAPFLGS is an AUTOGEN and DYNAMIC parameter.
16 – ACP_SYSACC
ACP_SYSACC sets the number of directory file control blocks
(FCBs) that are cached for disks mounted with the /SYSTEM
qualifier. Each directory FCB contains a 16-byte array containing
the first letter of the last entry in each block of the directory
(or group of blocks if the directory exceeds 16 blocks). Since
entries in a directory are alphabetical, the cached FCB provides
quick access to a required directory block. This parameter value
should be roughly equivalent to the number of directories that
are in use concurrently on each system volume. It might be
overridden on a per-volume basis with the /ACCESSED qualifier
to the DCL command MOUNT. The value should be kept low in systems
with small physical memory and little file activity, because
the FCBs require a significant amount of space in the nonpaged
dynamic pool.
Too small a value causes excessive XQP I/O operations, while too
large a value causes excessive physical memory to be consumed by
the FCB caches.
ACP_SYSACC is an AUTOGEN and DYNAMIC parameter.
17 – ACP_WINDOW
ACP_WINDOW sets the default number of window pointers to be
allocated in a window for a default file access, for disks
mounted with the /SYSTEM qualifier.
ACP_WINDOW is a DYNAMIC parameter.
18 – ACP_WORKSET
ACP_WORKSET sets the default size of a working set for an ACP.
A specification of 0 permits the ACP to calculate the size. This
value should be nonzero only on small systems where memory is
tight. Too small a value causes excessive ACP page, while too
large a value causes excessive physical memory to be consumed
by the ACP. Note that this parameter has no effect on the per-
process XQP.
ACP_WORKSET is a DYNAMIC parameter.
19 – ACP_WRITEBACK
ACP_WRITEBACK is a dynamic system parameter that controls whether
deferred writes to file headers are enabled. The default value is
1, which enables deferred writes to file headers. To disable the
feature, set ACP_WRITEBACK to 0.
This system parameter affects only applications like PATHWORKS
that can request deferred writes to file headers. Note that
the deferred write feature is not available on Files-11 ODS-1
volumes.
ACP_WRITEBACK is a DYNAMIC parameter.
20 – ACP_XQP_RES
ACP_XQP_RES controls whether the XQP is currently in memory.
The default value (1) specifies that the XQP is permanently in
memory. Change the default only on restricted memory systems
with a small number of users and little or no file activity that
requires XQP intervention. Such activity includes file opens,
closes, directory lookups, and window turns.
21 – AFFINITY_SKIP
AFFINITY_SKIP controls the breaking of implicit affinity. The
value indicates the number of times a process is skipped before
being moved.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
22 – AFFINITY_TIME
AFFINITY_TIME controls the breaking of implicit affinity. The
value indicates how long a process remains on the compute queue.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
23 – ALLOCLASS
ALLOCLASS determines the device allocation class for the system.
The device allocation class is used to derive a common lock
resource name for multiple access paths to the same device.
24 – ARB_SUPPORT
(Alpha and Integrity servers) The Access Rights Block (ARB)
compatibility option, the ARB_SUPPORT system parameter, is
provided specifically to support products that have not yet been
updated to use the new per-thread security Persona Security Block
(PSB) data structure instead of the ARB. Changing the value of
ARB_SUPPORT from 2 or 3 (the default) to any other value can
affect the operation of these products.
NOTE
VSI recommends that all Version 7.3-1 systems have the
ARB_SUPPORT parameter set to 3 (the default). Do not change
the ARB_SUPPORT parameter to any other value until all
products dependent on the ARB and associated structures
have been modified for the new environment.
The following table describes ARB_SUPPORT parameters:
ARB_SUPPORT
Parameter Value Behavior
ISS$C_ARB_NONE 0 The obsolete kernel data cells are not
maintained by the system. Fields are
initialized to zero (or set to invalid
pointers) at process creation.
ISS$C_ARB_CLEAR 1 The obsolete kernel data cells are
cleared (or set to invalid pointers)
when the code would have set up values
for backward compatibility.
ISS$C_ARB_READ_ 2 The obsolete cells are updated with
ONLY corresponding security information
stored in the current PSB when a
$PERSONA_ASSUME is issued.
ISS$C_ARB_FULL 3 (de- Data is moved from the obsolete cells
fault) to the currently active PSB on any
security-based operation.
ARB_SUPPORT is a DYNAMIC parameter.
25 – AUTO_DLIGHT_SAV
AUTO_DLIGHT_SAV is set to either 1 or 0. The default is 0.
If AUTO_DLIGHT_SAV is set to 1, OpenVMS automatically makes the
change to and from daylight saving time.
26 – AWSMIN
On Alpha and Integrity servers, AWSMIN establishes the lowest
number of pagelets to which a working set limit can be decreased
by automatic adjustment of the working set.
AWSMIN is a DYNAMIC parameter.
27 – AWSTIME
AWSTIME specifies the minimum amount of processor time that
must elapse for the system to collect a significant sample of
a working set's page fault rate. The time is expressed in units
of 10 milliseconds. The default value of 5, for example, is 50
milliseconds.
Some application configurations that have a large number of
memory-intensive processes may benefit if the value is reduced.
The value can be as low as 4.
AWSTIME expiration is checked only at quantum end. Reducing its
value and not reducing QUANTUM effectively sets the value of
AWSTIME equal to the value of QUANTUM.
AWSTIME is a DYNAMIC parameter.
28 – BALSETCNT
BALSETCNT sets the number of balance set slots in the system page
table. Each memory-resident working set requires one balance set
slot.
You can monitor the active system with the DCL command SHOW
MEMORY or the MONITOR PROCESSES command of the Monitor utility to
determine the actual maximum number of working sets in memory. If
this number is significantly lower than the value of BALSETCNT,
this parameter value could be lowered. If all balance set slots
are being used, raise the value of BALSETCNT.
Never set BALSETCNT to a value higher than 2 less than
MAXPROCESSCNT. If physical memory is a significant system
constraint, consider lowering this value even further. However,
if your system runs with a number of processes nearly equal to
MAXPROCESSCNT, lowering BALSETCNT forces swapping to occur, which
can affect system performance.
BALSETCNT is no longer a strict setting of the number of
processes that might be resident in memory. The swapper tries
to reduce the number of resident processes down to BALSETCNT.
However, if the total number of active processes and processes
that have disabled swapping exceeds BALSETCNT, the swapper does
not force processes out of memory just to meet the BALSETCNT
setting.
BALSETCNT is an AUTOGEN, GEN, DYNAMIC, and MAJOR parameter.
29 – BORROWLIM
BORROWLIM defines the minimum number of pages required on the
free-page list before the system permits process growth beyond
the working set quota (WSQUOTA) for the process. This parameter
should always be greater than FREELIM.
This parameter allows a process to grow beyond the value set by
the working set quota (WSQUOTA) to the working set quota extent
(WSEXTENT) on a system that has a substantial memory on the free-
page list. This automatic working set adjustment also depends
upon the values of parameters WSINC, PFRATH, and AWSTIME.
Working set growth attempts to alleviate heavy page faulting. To
make use of this growth, you must also set the user's WSEXTENT
authorization quota to a larger number than the WSQUOTA value.
BORROWLIM is an AUTOGEN, DYNAMIC and MAJOR parameter.
30 – BREAKPOINTS
If XDELTA is loaded, BREAKPOINTS enables additional built-in
calls for XDELTA during the boot sequence. The breakpoints that
are enabled may change from release to release of OpenVMS.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
BREAKPOINTS is a DYNAMIC parameter.
31 – BUGCHECKFATAL
BUGCHECKFATAL enables or disables the conversion of nonfatal
bugchecks into fatal bugchecks. The system must be rebooted on a
fatal bugcheck. A nonfatal bugcheck places an entry only in the
error log and deletes the corresponding process.
This parameter should normally be OFF (0); you should set it ON
(1) only when the executive is being debugged.
Setting the SYSTEM_CHECK parameter to 1 has the effect of setting
BUGCHECKFATAL to ON (1).
BUGCHECKFATAL is a DYNAMIC parameter.
32 – BUGREBOOT
BUGREBOOT enables or disables automatic rebooting of the system
if a fatal bugcheck occurs. This parameter should normally be on
(1); set it off (0) only when the executive is being debugged.
BUGREBOOT is a DYNAMIC parameter.
33 – CHANNELCNT
CHANNELCNT specifies the maximum number of I/O channels available
to processes and to the system. The FILLM quota can be used
to reduce the maximum number of I/O channels for a process. A
process with a FILLM quota larger than CHANNELCNT is nevertheless
limited to the maximum number of I/O channels specified by
CHANNELCNT.
34 – CLASS_PROT
CLASS_PROT performs the nondiscretionary classification
checks. CLASS_PROT is also checked by XQP to determine if a
classification block should be added to the header of any created
files.
CLASS_PROT is a DYNAMIC parameter.
35 – CLISYMTBL
CLISYMTBL sets the size of the command interpreter symbol table,
which controls the number of DCL symbols that can be created.
CLISYMTBL is a DYNAMIC parameter.
36 – CLUSTER_CREDITS
CLUSTER_CREDITS specifies the number of per-connection buffers a
node allocates to receiving VMS$VAXcluster communications.
If the SHOW CLUSTER command displays a high number of credit
waits for the VMS$VAXcluster connection, you might consider
increasing the value of CLUSTER_CREDITS on the other node.
However, in large cluster configurations, setting this value
unnecessarily high consumes a large quantity of nonpaged pool.
Each receive buffer is at least SCSMAXMSG bytes in size but might
be substantially larger depending on the underlying transport.
It is not required for all nodes in the cluster to have the same
value for CLUSTER_CREDITS.
The default value is currently 32. Unless a system has very
constrained memory available, VSI recommends that these values
not be increased.
37 – CONCEAL_DEVICES
CONCEAL_DEVICES enables or disables the use of concealed devices.
By default, this parameter is set to enable concealed devices
(1).
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
38 – CPU_POWER_MGMT_(D)
On Integrity servers, a CPU can be placed in "low-power mode"
when it is idle. This minimizes power consumption, thereby
reducing energy costs for the system. Beginning in Version 8.2-
1, OpenVMS Integrity servers supports this feature based on the
settings of two system parameters: CPU_POWER_MGMT and CPU_POWER_
THRSH.
A value of 1 for CPU_POWER_MGMT means on (the default); a value
of 0 means off. Whenever the CPU_POWER_THRSH parameter value is
exceeded, the operating system places an Integrity processor in
low-power mode if it is idle. OpenVMS Integrity servers does this
only if CPU_POWER_MGMT is on. A CPU returns to normal power when
it receives an interrupt.
CPU_POWER_MGMT is a DYNAMIC parameter.
39 – CPU_POWER_THRSH_(D)
On Integrity servers, CPU_POWER_THRSH is a parameter expressed
as a percentage. OpenVMS Integrity servers monitors how active
each CPU is over a fixed time period. If CPU_POWER_MGMT is on
and a CPU is idle for a period of time indicated by CPU_POWER_
THRSH, the CPU is placed in a low-power mode if it is idle. A CPU
returns to normal power when it receives an interrupt.
For systems supporting real-time operations that require quick
response time, VSI recommends that this feature be turned off. Use
of this feature can result in a small performance degradation.
For more information, see the Intel IA-64 Architecture Software
Developer's Manual, Volume 2: IA-64 System Architecture.
See also the CPU_POWER_MGMT parameter.
CPU_POWER_THRSH is a DYNAMIC parameter.
40 – CRD_CONTROL
This special parameter is use by VSI and is subject to change.
Do not change this parameter unless VSI recommends that you do so.
On Alpha and Integrity servers, CRD_CONTROL can be used to expand
the function defined by CRDENABLE.
CRD_CONTROL is a bit mask for corrected read data (CRD) soft
error control flags. These flags control the use of CRDERROR
routines.
On Alpha and Integrity servers, the following bits are defined:
Bit Description
0 Enables CRD processing for all systems.
1 Enables scrubbing (rewriting) of the memory location that
induced the CRD.
2 Enables page replacement of the pages that exhibit
repeated CRD errors.
3 Forces all memory pages to be included in the PFN
database. On systems that contain more than 512 megabytes
of memory, all memory is mapped by the PFN database by
default. This bit allows the mapping to occur on systems
with less than 512 megabytes of memory.
4 Enables extended CRD handling, if available.
5 Enables loading of driver and process for handling server
management events. Platform-specific code usually sets
this bit if the required hardware and firmware support are
available.
6 Disables CRD throttling.
7 Disables System Event Log (SEL) polling.
16-31 Reserved for platform-specific error-handling control.
On Alpha and Integrity servers, the default setting is 22, which
enables scrubbing, page replacement, and extended CRD handling.
41 – CRDENABLE
(Alpha and Integrity servers) CRDENABLE enables or disables
detection and logging of memory-corrected read data (ECC) errors.
This parameter should normally be set to (1).
Beginning with OpenVMS Version 7.2, CRD_CONTROL can expand the
function of CRDENABLE. (See CRD_CONTROL.)
42 – CTLIMGLIM
CTLIMGLIM specifies the size of the default image I/O segment;
that is channel table and initial buffer pool for image-related
file and RMS I/O.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
43 – CTLPAGES
CTLPAGES specifies the size of P1 pool. CTLPAGES is automatically
changed only when the process logical name table, DCL symbols, or
some layered products require an increase in the size of the P1
pool area.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
CTLPAGES is an AUTOGEN parameter.
44 – CWCREPRC_ENABLE
CWCREPRC_ENABLE controls whether an unprivileged user can create
a process on another OpenVMS Cluster node. The default value of 1
allows an unprivileged user to create a detached process with the
same UIC on another node. A value of 0 requires that a user have
DETACH or CMKRNL privilege to create a process on another node.
45 – DBGTK_SCRATCH
(Alpha and Integrity servers) DBGTK_SCRATCH specifies how many
pages of memory are allocated for the remote debugger. This
memory is allocated only if remote debugging is enabled with the
8000 boot flag. Normally, the default value is adequate, but if
the remote debugger issues an error message, you should increase
this value. See Writing OpenVMS Alpha Device Drivers in C (Margie
Sherlock and Lenny S. Szubowicz, Digital Press, 1996). for more
information. (This manual has been archived.)
46 – DCL_CTLFLAGS
DCL_CTLFLAGS is a bit mask that alters default behavior for
certain DCL-related functions on a systemwide basis. However,
the default values satisfy the needs of most systems.
Bits 0 and 2 control the formulation of system-generated process
names for processes created using the SPAWN command or LIB$SPAWN
library routine. They are provided for compatibility with
behavior of prior OpenVMS versions. Note that you can eliminate
the use of system-generated names by supplying your own process
names.
Bit 1 controls the token size used by DCL.
Bit 3 controls the maximum number input parameters to command
procedure.
Bit 4 controls the the maximum length for an user name, for which
OpenVMS mail forwarding address is set.
DCL_CTLFLAGS bits are described in the following table.
Bit Description
Bit If clear (the default), the numeric portion of a system-
0 generated spawned process name is generated randomly. If
set, the numeric portion is generated sequentially starting
with sequence number 1.
The option of sequential generation is provided for
compatibility with OpenVMS versions prior to Version
7.3-1. However, this choice can be very expensive in
performance terms because of the mechanism for finding
the next available process name. This mechanism attempts to
create all process names beginning with sequence number 1
until it finds one that is unused.
Random generation is the preferred choice because it
results in a very high probability of finding a unique
name on the first try.
Bit Controls the token size used by DCL. If clear (the
1 default), this bit instructs DCL to use the traditional
token size. A token cannot exceed 255 characters. If this
bit is set, extended tokens are used. Extended tokens are
4000 characters.
Note that if you turn on extended tokens, file
specifications can exceed 255 characters, which might
require larger structures for parsing file specifications.
Bit If clear (the default), the numeric portion of a system-
2 generated spawned process name has a maximum value of
65535. If set, the numeric portion of the name has a
maximum value of 255.
The option of a maximum of 255 is provided for
compatibility with OpenVMS versions prior to Version 8.3,
when it was the only choice. The larger maximum allows many
more unique spawned process names for a given process.
For this reason, it is the preferred choice. However,
the larger maximum uses two additional characters from
the process name, which might make it more difficult to
identify users uniquely by looking at their spawned process
names. If this is an issue on your system, setting bit 2
might be a better choice.
Bit If clear (the default), command procedure supports the
3 default eight optional parameters (that is, (P1,P2,...P8)).
If set, command procedure supports up to sixteen optional
parameters (that is, (P1,P2,...P16)). This is also
applicable when using the CALL command to transfer control
to a subroutine.
Bit This bit controls the the maximum length for an user name,
4 for which OpenVMS mail forwarding address is set. If clear
(the default), user name string length is set to a maximum
length of 31 characters. If set, user name string length is
set to a maximum of 255 characters.
Note: Once this bit is set, user name length is set to
maximum of 255 characters. Even if this bit is cleared,
the behavior remains unchanged, that is, supports user name
length of 255 characters, but there is no way to reset it
to 31 characters.
47 – DEADLOCK_WAIT
DEADLOCK_WAIT defines the number of seconds that a lock request
must wait before the system initiates a deadlock search on behalf
of that lock. Setting DEADLOCK_WAIT to zero disables deadlock
checking. Setting DEADLOCK_WAIT to a value greater than zero
and less than the default setting provides faster detection of
deadlocks but requires more CPU usage.
The DEADLOCK_WAIT value is expressed in seconds; therefore, the
smallest value you can set is 1 second. Beginning in VSI OpenVMS
Version 8.3, a subsecond deadlock wait time, which is set in
the system service $SET_PROCESS_PROPERTIESW item code $PPROP$C_
DEADLOCK_WAIT, overrides DEADLOCK_WAIT. For more information, see
the $SET_PROCESS_PROPERTIESW system service in VSI OpenVMS System
Services Reference Manual.
DEADLOCK_WAIT is a DYNAMIC parameter.
48 – DEFGID
Default POSIX GID used internally by OpenVMS.
49 – DEFMBXBUFQUO
DEFMBXBUFQUO sets the default for the mailbox buffer quota size
in bytes when this value is not specified in a Create Mailbox
($CREMBX) system service call.
DEFMBXBUFQUO is a DYNAMIC parameter.
50 – DEFMBXMXMSG
DEFMBXMXMSG sets the default for the mailbox maximum message size
in bytes when this value is not specified in a Create Mailbox
($CREMBX) system service call.
DEFMBXMXMSG is a DYNAMIC parameter.
51 – DEFPRI
DEFPRI sets the base default priority for processes.
DEFPRI is a DYNAMIC parameter.
52 – DEFQUEPRI
DEFQUEPRI establishes the scheduling priority for jobs entered
in batch and output (printer, server, and terminal) queues when
no explicit scheduling priority is specified by the submitter.
The value of this parameter can range from 0 to 255; the default
value is 100.
The value of DEFQUEPRI should be less than or equal to MAXQUEPRI.
NOTE
DEFQUEPRI refers to relative queue scheduling priority, not
the execution priority of the job.
DEFQUEPRI is a DYNAMIC parameter.
53 – DEFUID
Default POSIX UID used internally by OpenVMS.
54 – DELPRC_EXIT
DELPRC_EXIT can be used to control $DELPRC system service options
that call exit handlers prior to final cleanup and deletion of a
process. The following table describes these options:
Option Description
0 Disable the exit handler functionality with
$DELPRC.
4 Execute kernel mode exit handlers.
5 (default) Execute exec and more privileged mode exit
handlers.
6 Execute supervisor and more privileged mode exit
handlers.
7 Execute user and more privileged mode exit
handlers.
DELPRC_EXIT is a DYNAMIC parameter.
55 – DEVICE_NAMING
(Alpha and Integrity servers) DEVICE_NAMING is a bit mask
indicating whether port allocation classes are used in forming
SCSI device names.
Following is the bit definition:
Bit Definition
0 If 1, enable new naming.
1 Must be 0. This bit is Reserved for use by VSI.
2 If 1, cloned device unit numbers wrap after 9999(not 65472).
3 If 1, cloned device unit numbers wrap after 32767(not 65472).
Note that even if both bits are zero, device unit numbers will
wrap after 9999 if "nodename$" is prefixed to the name of the
device in question (e.g. VMS123$DKA100:); devices whose drivers
support larger device numbers will wrap after 65472 (or 32767
if bit 3 is set) only if the nodename is not built into the
device name.
For more information about port allocation classes, see the VSI
OpenVMS Cluster Systems manual.
56 – DISABLE_UPCALLS
DISABLE_UPCALLS is primarily a debugging aid. It allows the
system manager to disable threads upcalls of specific types
for the entire system. The value is a bit mask, with the bits
corresponding to the upcall types. The upcall types are defined
in the definition macro $TMCDEF.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
DISABLE_UPCALLS is a DYNAMIC parameter.
57 – DISK_QUORUM
The DISK_QUORUM parameter is the name of an optional quorum disk
in ASCII. ASCII spaces indicate that no quorum disk is being
used.
58 – DISMOUMSG
DISMOUMSG controls whether the messages that log volume dismounts
appear on the operator's terminal and in the operator's log. The
default value of 0 disables reporting of these messages.
DISMOUMSG is a DYNAMIC parameter.
59 – DNVOSI1
DNVOSI1 is reserved to DECnet-Plus for OpenVMS. This special
parameter is use by VSI and is subject to change. Do not change
this parameter unless VSI recommends that you do so.
60 – DORMANTWAIT
DORMANTWAIT specifies, in seconds, the amount of time that can
elapse without a significant event before the system treats
a low-priority computable process as a DORMANT process for
scheduling purposes. (A low-priority process is a non real-time
process whose current priority is equal to or less than the value
specified by the system parameter DEFPRI [default=4].) After
SUSP (suspended) processes, DORMANT processes are the most likely
candidates for memory reclamation by the swapper.
Increasing the value of DORMANTWAIT can increase the interval
that a low priority process blocks a high priority process if
that low priority process is holding a lock or resource that the
higher priority process is waiting for.
DORMANTWAIT is a DYNAMIC parameter.
61 – DR_UNIT_BASE
(Alpha only) DR_UNIT_BASE specifies the base value from which
unit numbers for DR devices (DIGITAL StorageWorks RAID Array 200
Family logical RAID drives) are counted.
DR_UNIT_BASE provides a way for unique RAID device numbers to
be generated. DR devices are numbered starting with the value of
DR_UNIT_BASE and then counting from there. For example, setting
DR_UNIT_BASE to 10 produces device names such as $1$DRA10,
$1$DRA11, and so on.
Setting DR_UNIT_BASE to appropriate, nonoverlapping values on all
cluster members that share the same (nonzero) allocation class
ensures that no two RAID devices are given the same name.
DR_UNIT_BASE is a GEN parameter.
62 – DUMPBUG
DUMPBUG enables (1) or disables (0) the writing of error log
buffers and memory contents to SYS$SYSTEM:SYSDUMP.DMP when a
fatal bugcheck occurs. This parameter should be off (0) only
when the executive is being debugged.
63 – DUMPSTYLE
DUMPSTYLE specifies the method of writing system dumps.
DUMPSTYLE is a 32-bit mask, with the following bits defined.
Each bit can be set independently. The value of the system
parameter is the sum of the values of the bits that have been
set. Remaining or undefined values are reserved for VSI use only.
Bit Mask Description
0 00000001 0 = Full dump (SYSGEN default).
The entire contents of physical
memory are written to the dump
file.
1 = Selective dump. The contents of
memory are written to the dump
file selectively to maximize
the usefulness of the dump file
while conserving disk space.
1 00000002 0 = Minimal console output.
1 = Full console output (includes
stack dump, register contents,
and so on).
2 00000004 0 = Dump to system disk.
1 = Dump off system disk (DOSD) to
an alternate disk. (see the VSI
OpenVMS System Manager's Manual
for details.)
3 (Alpha and 00000008 0 = Do not compress.
Integrity
servers)
1 = Compress. (VAX systems do not
support dump compression.)
4 (Alpha and 00000010 0 = Dump shared memory.
Integrity
servers)
1 = Do not dump shared memory. (VAX
systems do not support shared
memory.)
5 - 14 reserved for VSI use only.
15 (VAX only) 00008000 0 = Disable use of bits 16 - 27.
(Specific to VAX 7000s.)
1 = Enable use of bits 16 - 27.
16 - 27 (VAX 0FFF0000 Range of DOSD unit numbers. (VAX
only) systems do not support shared
memory.)
28 - 31 reserved for VSI use only.
If you plan to enable the Volume Shadowing minimerge feature on
an Alpha or Integrity servers disk, be sure to specify DOSD to an
alternate disk.
NOTE
On Alpha and Integrity servers, you can save space on
the system disk and, in the event of a crash, save time
recording the system memory, by using the OpenVMS Alpha
and Integrity servers dump compression feature. Unless
you override the default AUTOGEN calculations (by setting
DUMPSTYLE in MODPARAMS.DAT), AUTOGEN uses the following
algorithm:
o On a system with less than 128 MB of memory, the system
sets the DUMPSTYLE to 1 (a raw selective dump) and sizes
the dump file appropriately.
o On a system with 128 MB of memory or greater, the system
sets the DUMPSTYLE to 9 (a compressed selective dump),
and creates the dump file at two-thirds the value of the
corresponding raw dump.
Examples:
The mask of 00000006 directs the system to send a full dump, with
full console output, off the system disk (to the alternate disk).
For a VAX 7000, a mask of 00098006 directs the system to send a
full dump with full console output to the DOSD whose unit number
is 9.
On Alpha and Integrity servers, the mask of 00000009 directs the
system to compress a selective dump with minimal console output.
DUMPSTYLE has AUTOGEN and DYNAMIC attributes.
64 – ERLBUFFERPAG_S2
ERLBUFFERPAG_S2 specifies the amount of S2 space memory to
allocate for each S2 space error log buffer requested by the
ERRORLOGBUFF_S2 parameter.
If you increase ERLBUFFERPAG_S2, you must either run AUTOGEN or
manually increase the size of both the system dump file and the
error log dump file.
ERLBUFFERPAG_S2 is an AUTOGEN parameter on Alpha and Integrity
servers.
65 – ERLBUFFERPAGES
ERLBUFFERPAGES specifies the amount of S0 space memory to
allocate for each S0 space error log buffer requested by the
ERRORLOGBUFFERS parameter.
ERLBUFFERPAGES is an AUTOGEN parameter on Alpha and Integrity
servers.
66 – ERRORLOGBUFF_S2
ERRORLOGBUFF_S2 specifies the number of S2 space error log
buffers reserved for system error log entries. Each buffer
is ERLBUFFERPAG_S2 in length. If ERRORLOGBUFF_S2 is too low,
messages might not be written to the error log file. If it is too
high, the buffers can consume unnecessary physical pages.
If you increase ERRORLOGBUFF_S2, you must either run AUTOGEN or
manually increase the size of both the system dump file and the
error log dump file.
ERRORLOGBUFF_S2 is an AUTOGEN parameter on Alpha and Integrity
servers.
67 – ERRORLOGBUFFERS
ERRORLOGBUFFERS specifies the number of S0 space error log
buffers reserved for system error log entries. Each buffer is
ERLBUFFERPAGES in length. If ERRORLOGBUFFERS is too low, messages
might not be written to the error log file. If it is too high,
the buffers can consume unnecessary physical pages.
ERRORLOGBUFFERS is an AUTOGEN parameter on Alpha and Integrity
servers.
68 – EXECSTACKPAGES
(Alpha and Integrity servers) EXECSTACKPAGES controls the number
of pages allocated for each RMS exec stack.
EXECSTACKPAGES is a DYNAMIC parameter.
69 – EXPECTED_VOTES
EXPECTED_VOTES specifies the maximum number of votes that can be
present in a cluster at any given time. Set it to a value that is
equal to the sum of the vote parameters of all cluster members,
plus any votes that are contributed by the quorum disk. This
value is used to automatically derive the number of votes that
must be present for the cluster to function (quorum).
EXPECTED_VOTES is an AUTOGEN attribute parameter.
70 – EXTRACPU
EXTRACPU sets the time, in units of 10 ms, allotted to each of a
process's exit handlers (for each access mode) after the process
times out (that is, reaches its CPU time limit).
EXTRACPU is a DYNAMIC attribute parameter.
71 – FAST_PATH
(Alpha and Integrity servers) FAST_PATH is a static system
parameter that enables (1) or disables (0) the Fast Path
performance features for all Fast Path-capable ports.
Starting in OpenVMS Version 7.2, FAST_PATH is enabled by default.
In Versions 7.0 and 7.1, FAST_PATH was disabled by default.
For additional information, see FAST_PATH_PORTS.
72 – FAST_PATH_PORTS
(Alpha and Integrity servers) FAST_PATH_PORTS is a static
parameter that deactivates Fast Path for specific drivers.
FAST_PATH_PORTS is a 32-bit mask, with a bit assigned for each
Fast Path port driver. The following table describes the bit
values:
Bit
Value Description
1 Indicates that Fast Path is disabled for ports serviced
by the corresponding driver.
0 Indicates that Fast Path is not disabled for ports
serviced by the corresponding driver.
Beginning in OpenVMS Version 7.3-1, values of specific bit
positions are those described in the following table:
Bit
Position Description
0 Controls Fast Path for PKQDRIVER (for parallel SCSI).
1 Controls Fast Path for FGEDRIVER (for Emulex LP7000,
LP8000, LP9002, LP9802, LP10000 FibreChannel).
2 Controls Fast Path for PKADRIVER (for Adaptec AIC-78xx
Ultra3 SCSI).
3 Controls Fast Path for PEDRIVER (for LAN).
4 Controls Fast Path for PKRDRIVER (for SMART Array 5300).
5 Controls Fast Path for PKMDRIVER, the LSI Logic
LSI53C1030 SCSI port driver.
6 Controls Fast Path for PGQDRIVER, the Qlogic ISP23xx
FibreChannel port driver.
Currently, the default setting for FAST_PATH_PORTS is 0, which
means that Fast Path is enabled for all drivers that appear in
the table.
In addition, note the following:
o CI drivers are not controlled by FAST_PATH_PORTS. Fast Path
for CI is enabled and disabled exclusively by the FAST_PATH
system parameter.
o FAST_PATH_PORTS is relevant only if the FAST_PATH system
parameter is enabled (equal to 1). Setting FAST_PATH to zero
has the same effect as setting all the bits in FAST_PATH_PORTS
to 1.
For additional information, see FAST_PATH. For an explanation of
how to set the bits, see the OpenVMS I/O User's Reference Manual.
73 – FREEGOAL
FREEGOAL establishes the number of pages that you want to
reestablish on the free-page list following a system memory
shortage. Memory shortages occur when the system drops below the
minimum number of pages required on the free-page list (FREELIM).
The value of FREEGOAL must always be greater than or equal to the
value of FREELIM.
FREEGOAL has the AUTOGEN, DYNAMIC, and MAJOR attributes.
74 – FREELIM
FREELIM sets the minimum number of pages that must be on the
free-page list.
The system writes pages from the modified-page list, swaps out
working sets, or reduces the size of the working sets to maintain
the minimum count.
While the larger free-page list generally means less page I/O, it
also means less space for the balance set, which tends to result
in more swap I/O. You can monitor the size of the free-page list,
the amount of page, and the amount of swap with the MONITOR IO
command of the Monitor utility.
FREELIM has the AUTOGEN and MAJOR attributes.
75 – GALAXY
(Alpha Galaxy platforms only) The GALAXY parameter sets memory
sharing.
Specify one of the following:
Value Description
0 The default. Do not participate in a memory sharing.
1 Participate in a memory sharing.
When you set GALAXY to 1 in a hard partition, OpenVMS instances
will share memory between soft partitions within that hard
partition. (You can run more than two soft partitions in a hard
partition, and you might might not want to share memory among all
of them.) Note that GALAXY specifies only if a node uses shared
memory. You do not need to use the parameter to run multiple
cooperative instances of OpenVMS; you do this by console setup of
the configuration tree that you want.
76 – GBLPAGES
GBLPAGES sets the number of global page table entries allocated
at bootstrap time. Each global section requires 1 global page
table entry per section page, plus 2 entries, with the total
rounded up to an even number.
Users with CMKRNL privilege can change this parameter on a
running system. Increasing the value of this parameter allows
the global page table to expand, on demand, up to the maximum
size.
The default value is sufficient for the images normally installed
as shared in the system startup command procedures. Once the
system is running and all global sections are created, you can
examine the actual requirements with the /GLOBAL qualifier of
the Install utility (INSTALL) and reduce the value of GBLPAGES
accordingly. However, do not set the value of this parameter
too low, because the page table entries use little permanently
resident memory. If you plan to install many user images as
shared, or if user programs are likely to create many global
sections, you must increase the value of this parameter.
GBLPAGES has the AUTOGEN, DYNAMIC, FEEDBACK, GEN, and MAJOR
attributes.
77 – GBLPAGFIL
GBLPAGFIL defines the maximum number of systemwide pages allowed
for global page-file sections (scratch global sections that can
be used without being mapped to a file). These global page-
file sections can be temporary, permanent, system, or group,
and are allocated from the page file specified in the system
process header at bootstrap time. When you allow pages for
global page-file sections, you must increase the size of the
page file accordingly. Users with CMKRNL privilege can change
this parameter value on a running system.
Global page-file sections are created with the Create and Map
Section system services ($CREATE_GPFILE, $CRMPSC, and $CRMPSC_
GPFILE_64) without an explicit disk file. These sections are used
for the RMS global buffers required for shared files. Users of
shared files should note that global page-file sections cause
both the global page table and the default system page file
(PAGEFILE.SYS) to be used. If the value of GBLPAGFIL is too
small, $CRMPSC issues an error message when you attempt to create
global page-file sections.
You must have scratch global sections if you use RMS global
buffers. Each file using global buffers requires, in the system
page file, the file's bucket size multiplied by the number of
global buffers for that file. If the file's bucket size varies,
as with RMS indexed files, use the maximum bucket size. For
shared sequential files, use the multiblock count of the first
stream to perform the $CONNECT service in place of the file's
bucket size.
The default value for this parameter is adequate for most
systems. However, if your site uses RMS global buffering to a
significant extent, you may need to raise the value of GBLPAGFIL.
Use the /GLOBAL qualifier of the Install utility to examine
the number of pages consumed by RMS global buffers. The global
sections used by RMS for global buffers have the prefix RMS$
followed by 8 hexadecimal digits.
Global buffers are enabled with the DCL command SET
FILE/GLOBAL_BUFFERS, which is described in the VSI OpenVMS DCL
Dictionary.
GBLPAGFIL is an AUTOGEN-altered and a DYNAMIC parameter.
78 – GBLSECTIONS
GBLSECTIONS sets the number of global section descriptors
allocated in the system header at bootstrap time. Each global
section requires one descriptor. Each descriptor takes 32 bytes
of permanently resident memory.
The default value is sufficient for the images normally installed
as shared in the system startup command procedures. Once the
system is running and all global sections are created, you can
examine the actual requirements with the /GLOBAL qualifier of the
Install utility and reduce the value of GBLSECTIONS accordingly.
However, the value of this parameter should not be set too low.
If you plan to install many user images as shared, or if user
programs are likely to create many global sections, you must
increase the value of this parameter.
If the value of GBLSECTIONS is too small, you receive a message
from the Install utility at system startup time or whenever
you install images manually. Note that too large a value for
GBLSECTIONS wastes physical memory.
GBLSECTIONS has the AUTOGEN, FEEDBACK, GEN, and MAJOR attributes.
79 – GB_CACHEALLMAX
(Alpha and Integrity servers) If a file is connected to RMS with
the RMS global buffer DEFAULT option enabled, the number of of
blocks cached is either a maximum of the GB_CACHEALLMAX parameter
or a percentage of the file, whichever results in a larger global
count.
Note that although a maximum cache size of %x7FFFFFFF is
supported for an indexed file, sequential and relative file
organizations are restricted to a maximum cache size of 32767.
GB_CACHEALLMAX is a DYNAMIC parameter.
80 – GB_DEFPERCENT
(Alpha and Integrity servers) If a file is connected to RMS with
the RMS global buffer DEFAULT option enabled, either a percentage
(GB_DEFPERCENT) of the file is cached or up to GB_CACHEALLMAX
blocks of it are cached, whichever results in a larger global
buffer count. A percentage greater than 100 percent can be
specified for GB_DEFPERCENT to provide growing room for a file
in the global cache.
Note that although a maximum cache size of %x7FFFFFFF is
supported for an indexed file, sequential and relative file
organizations are restricted to a maximum cache size of 32767.
GB_DEFPERCENT is a DYNAMIC parameter.
81 – GH_EXEC_CODE
(Alpha and Integrity servers) GH_EXEC_CODE specifies the size in
pages of the execlet code granularity hint region.
GH_EXEC_CODE has the AUTOGEN and FEEDBACK attributes.
82 – GH_EXEC_DATA
(Alpha and Integrity servers) GH_EXEC_DATA specifies the size in
pages of the execlet data granularity hint region.
GH_EXEC_DATA has the AUTOGEN and FEEDBACK parameters.
83 – GH_RES_CODE
(Alpha and Integrity servers) GH_RES_CODE specifies the size in
pages of the resident image code granularity hint region.
GH_RES_CODE has the AUTOGEN and FEEDBACK attributes.
84 – GH_RES_CODE_S2
Specifies the size in pages of the resident 64-bit S2 space
resident image code granularity hint region.
85 – GH_RES_DATA
(Alpha and Integrity servers) GH_RES_DATA specifies the size in
pages of the resident image data granularity hint region.
If bit 2 of the LOAD_SYS_IMAGES parameter is set, the image
LDR$WRAPUP releases all unused pages in the granularity hint
region at the the end of system startup. The unused pages of the
resident image granularity hint region are either reserved for
future use, or given back to the free memory list.
GH_RES_DATA has the AUTOGEN and FEEDBACK attributes.
86 – GH_RSRVPGCNT
GH_RSRVPGCNT specifies the number of pages in the resident image
code granularity hint region that the Install utility can use
after the system has finished booting.
If bit 2 of the LOAD_SYS_IMAGES parameter is set, the image
LDR$WRAPUP releases all unused pages in the granularity hint
region at the the end of system startup. The unused pages of the
resident image granularity hint region are either reserved for
future use, or given back to the free memory list.
GH_RSRVPGCNT specifies the number of pages that LDR$WRAPUP
attempts to leave in the resident image code granularity hint
region. If the GH_RSRVPGCNT number of pages is larger than the
unused pages in the granularity hint region, the region is not
expanded to accommodate the number of pages requested.
GH_RSRVPGCNT is a FEEDBACK attribute parameter.
87 – GLX_INST_TMO
(Alpha Galaxy platforms only) GLX_INST_TMO is the time (in
milliseconds) that an instance in a Galaxy sharing set can fail
to increment its timeout value before the other sharing instances
presume that the instance failed and remove it from the sharing
set.
The default is 20,000 ms (20 seconds).
88 – GLX_SHM_REG
For Alpha Galaxy systems, GLX_SHM_REG is the number of shared
memory region structures configured into the Galaxy Management
Database (GMDB). If set to 0, the default number of shared memory
regions are configured.
If the condition value SS$_INSF_SHM_REG is returned for the
$CRNMPSC_GDZRO_64 system service with the flag SEC$M_SHM_REG, the
Galaxy shared memory code has run out of internal SHM_REG data
structures. You need to increase the system parameter GLX_SHM_REG
and reboot all Galaxy instances with this larger parameter value.
89 – GROWLIM
GROWLIM sets the number of pages that the system must have on the
free-page list so that a process can add a page to its working
set when it is above quota. GROWLIM has no effect if the process
is below its working set quota. GROWLIM acts as a fast shutoff
to the working set extent mechanism based on the system's free
memory.
GROWLIM has AUTOGEN, DYNAMIC, and MAJOR attributes.
90 – IEEE_ADDRESS
IEEE_ADDRESS is reserved for VSI use only.
91 – IEEE_ADDRESSH
IEEE_ADDRESSH is reserved for VSI use only.
92 – IJOBLIM
IJOBLIM sets the maximum number of interactive jobs that can be
on the system concurrently. You can control the maximum number of
concurrent interactive users on the system with the DCL command
SET LOGINS/INTERACTIVE.
IJOBLIM is a DYNAMIC parameter.
93 – IMGIOCNT
IMGIOCNT specifies the default number of pages of image I/O
address space to be allocated for the image activator if not
specified at program link time.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
94 – IMGREG_PAGES
(Alpha and Integrity servers) IMGREG_PAGES is the number of
pages to reserve in P1 space for images to be installed with
shareable address data. If IMGREG_PAGES is set to 0, no images
are installed with shared address data. The default is 10,000
pages.
For more information, see the INSTALL section in the VSI OpenVMS
System Management Utilities Reference Manual.
95 – IO_PRCPU_BITMAP
(Alpha and Integrity servers) This parameter is a bitmap
representing up to 1024 CPUs. Each bit set in this bitmap
indicates that the corresponding CPU is available for use as a
Fast Path preferred CPU.
IO_PRCPU_BITMAP defaults to all bits set. (CPU 0 through CPU 1023
are all enabled for Fast Path port assignment.)
You might want to disable the primary CPU from serving as a
preferred CPU by leaving its bit clear in IO_PRCPU_BITMAP, which
reserves the primary CPU for non-Fast Path IO operations to use.
To change the value of IO_PRCPU_BITMAP in SYSBOOT or SYSGEN,
specify a list of individual bits or contiguous groups of bits.
For example:
SYSGEN> SET IO_PRCPU_BITMAP 0,5,17-21
This command sets bits 0, 5, 17, 18, 19, 20, and 21 in the bitmap
and clears all other bits.
Changing the value of IO_PRCPU_BITMAP causes the FASTPATH_SERVER
process to run the automatic assignment algorithm that spreads
Fast Path ports evenly among the new set of usable CPUs.
For additional information, see FAST_PATH and FAST_PATH_PORTS.
This parameter replaces IO_PREFER_CPU.
96 – IOTA
IOTA specifies the amount of time (in 10-millisecond units) to
charge to the current residence quantum for each voluntary wait.
The correct value approximates the cost of a disk I/O neglecting
wait time.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
97 – IRPCOUNT
IRPCOUNT sets the number of preallocated intermediate request
packets. Each packet requires 160 bytes of permanently resident
memory. If IRPCOUNT is too large, physical memory is wasted.
If IRPCOUNT is too small, the system increases its value
automatically, as needed, to permit proper performance.
However, the system cannot increase IRPCOUNT beyond the value
of IRPCOUNTV.
Allowing this growth causes a physical memory penalty. If
IRPCOUNT is underconfigured, the penalty is 4 percent of physical
memory from the configured value to the actual value on the
running system.
You can use the DCL command SHOW MEMORY/POOL/FULL to determine
IRPCOUNT usage.
IRPCOUNT has the GEN and MAJOR attributes.
98 – IRPCOUNTV
IRPCOUNTV establishes the upper limit to which IRPCOUNT can be
automatically increased by the system.
If this parameter is set too low, system performance can be
adversely affected because IRPCOUNTV cannot be used for nonpaged
pool requests.
A physical memory penalty of 1 percent results for any unused
growth space (1 longword for every 3 unused intermediate request
packets).
IRPCOUNTV has the GEN attribute.
99 – JBOBLIM
This parameter is no longer in use.
100 – JOBCTLD
System managers do not usually alter JOBCTLD; this word of debug
flags is used in rolling upgrades of OpenVMS. If bit 0 is set,
the queue manager does not start. The default is 0.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
101 – KSTACKPAGES
(Alpha and Integrity servers) KSTACKPAGES controls the number of
pages allocated for process kernel stacks.
102 – LAN_FLAGS
(Alpha and Integrity servers) LAN_FLAGS is a bit mask used to
enable features in the local area networks port drivers and
support code. The default value for LAN_FLAGS is 0.
The bit definitions are as follows:
Bit Description
0 The default of zero indicates that ATM devices run in
SONET mode. If set to 1, this bit indicates ATM devices
run in SDH mode.
1 If set, this bit enables a subset of the ATM trace
and debug messages in the LAN port drivers and support
code.
2 If set, this bit enables all ATM trace and debug
messages in the LAN port drivers and support code.
3 If set, this bit runs UNI 3.0 over all ATM adapters.
(Auto-sensing of the ATM UNI version is enabled if both
bit 3 and bit 4 are off (0).)
4 If set, this bit runs UNI 3.1 over all ATM adapters.
(Auto-sensing of the ATM UNI version is enabled if both
bit 3 and bit 4 are off (0).)
5 If set, disables auto-negotiation over all Gigabit
Ethernet Adapters.
6 If set, enables the use of jumbo frames over all
Gigabit Ethernet Adapters.
7 Reserved.
8 If set, disables the use of flow control over all LAN
adapters that support flow control.
9 Reserved.
10 Reserved.
11 If set, disables the logging of error log entries by
LAN drivers.
12 If set, enables a fast timeout on transmit requests,
usually between 1 and 1.2 seconds instead of 3 to 4
seconds, for most LAN drivers.
13 If set, transmits that are given to the LAN device
and never completed by the device (transmit timeout
condition) are completed with error status (SS$_ABORT)
rather than success status (SS$_NORMAL).
LAN_FLAGS is a DYNAMIC parameter.
103 – LCKMGR_CPUID
(Alpha and Integrity servers) LCKMGR_CPUID controls the CPU that
the Dedicated CPU Lock Manager runs on. This is the CPU that the
LCKMGR_SERVER process utilizes if you turn this feature on with
the LCKMGR_MODE system parameter.
If the specified CPU ID is either the primary CPU or a
nonexistent CPU, the LCKMGR_SERVER process utilizes the lowest
nonprimary CPU. For more information, see the LCKMGR_MODE system
parameter.
LCKMGR_CPUID is a DYNAMIC parameter.
104 – LCKMGR_MODE
(Alpha and Integrity servers) The LCKMGR_MODE parameter controls
use of the Dedicated CPU Lock Manager. Setting LCKMGR_MODE to a
number greater than zero (0) indicates the number of CPUs that
must be active before the Dedicated CPU Lock Manager is turned
on.
The Dedicated CPU Lock Manager performs all locking operations
on a single dedicated CPU. This can improve system performance
on large SMP systems with high MP_Synch associated with the lock
manager.
If the number of active CPUs is greater than or equal to LCKMGR_
MODE, a LCKMGR_SERVER process is created to service locking
operations. This process runs at a real-time priority of 63 and
is always current.
In addition, if the number of active CPUs should ever be reduced
below the required threshold by either a STOP/CPU command or by
a CPU reassignment in a Galaxy configuration, the Dedicated CPU
Lock Manager automatically turns off within one second, and the
LCKMGR_SERVER is placed in a hibernate state. If the number of
active CPUs is increased, the LCKMGR_SERVER resumes servicing
locking operations.
Specify one of the following:
o Zero (0) indicates that the Dedicated CPU Lock Manager is off
(the default).
o A number greater than zero (0) indicates the number of CPUs
that must be active before the Dedicated CPU Lock Manager will
turn on.
When the Dedicated CPU Lock Manager is turned on, fast path
devices are not assigned to the CPU used by the Dedicated CPU
Lock Manager.
When the Dedicated CPU Lock Manager is turned on, fast path
devices are not assigned to the CPU used by the Dedicated CPU
Lock Manager.
For more information about use of the Dedicated CPU Lock Manager,
see the OpenVMS Performance Management manual.
LCKMGR_MODE is a DYNAMIC parameter.
105 – LGI_BRK_DISUSER
LGI_BRK_DISUSER turns on the DISUSER flag in the UAF record when
an attempted break-in is detected, thus permanently locking
out that account. The parameter is off (0) by default. You
should set the parameter (1) only under extreme security watch
conditions, because it results in severely restricted user
service.
LGI_BRK_DISUSER is a DYNAMIC parameter.
106 – LGI_BRK_LIM
LGI_BRK_LIM specifies the number of failures that can occur at
login time before the system takes action against a possible
break-in. The count of failures applies independently to login
attempts by each user name, terminal, and node. Whenever login
attempts from any of these sources reach the break-in limit
specified by LGI_BRK_LIM, the system assumes it is under attack
and initiates evasive action as specified by the LGI_HID_TIM
parameter.
The minimum value is 1. The default value is usually adequate.
LGI_BRK_LIM is a DYNAMIC parameter.
107 – LGI_BRK_TERM
LGI_BRK_TERM causes the terminal name to be part of the
association string for the terminal mode of break-in detection.
When LGI_BRK_TERM is set to off (0), the processing considers
the local or remote source of the attempt, allowing break-in
detection to correlate failed access attempts across multiple
terminal devices. When set to on (1), LGI_BRK_TERM assumes that
only local hard-wired or dedicated terminals are in use and
causes breakin detection processing to include the specific local
terminal name when examining and correlating break-in attempts.
Ordinarily, LGI_BRK_TERM should be set to off (0) when physical
terminal names are created dynamically, such as when network
protocols like LAT and Telnet are in use.
LGI_BRK_TERM is a DYNAMIC parameter.
108 – LGI_BRK_TMO
LGI_BRK_TMO specifies the length of the failure monitoring
period. This time increment is added to the suspect's expiration
time each time a login failure occurs. Once the expiration period
passes, prior failures are discarded, and the suspect is given a
clean slate.
LGI_BRK_TMO is a DYNAMIC parameter.
109 – LGI_CALLOUTS
LGI_CALLOUTS specifies the number of installation security policy
callout modules to be invoked at each login. LGI_CALLOUTS must be
set to 0 unless callout modules are present.
LGI_CALLOUTS is a DYNAMIC parameter.
110 – LGI_HID_TIM
LGI_HID_TIM specifies the number of seconds that evasive action
persists following the detection of a possible break-in attempt.
The system refuses to allow any logins during this period, even
if a valid user name and password are specified.
LGI_HID_TIM is a DYNAMIC parameter.
111 – LGI_PWD_TMO
LGI_PWD_TMO specifies, in seconds, the period of time a user
has to enter the correct system password (if used). LGI_PWD_TMO
also establishes the timeout period for users to enter their
personal account passwords at login time. Also, when using the
SET PASSWORD command, LGI_PWD_TMO specifies the period of time
the system waits for a user to type in a new password, an old
password, and the password verification.
LGI_PWD_TMO is a DYNAMIC parameter.
112 – LGI_RETRY_LIM
LGI_RETRY_LIM specifies the number of retry attempts allowed
users attempting to log in. If this parameter is greater than 0,
and a legitimate user fails to log in correctly because of typing
errors, the user does not automatically lose the carrier. Instead
(provided that LGI_RETRY_TMO has not elapsed), by pressing the
Return key, the user is prompted to enter the user name and
password again. Once the specified number of attempts has been
made without success, the user loses the carrier. As long as
neither LGI_BRK_LIM nor LGI_BRK_TMO has elapsed, the user can
dial in again and reattempt login.
LGI_RETRY_LIM is a DYNAMIC parameter.
113 – LGI_RETRY_TMO
LGI_RETRY_TMO specifies the number of seconds allowed between
login retry attempts after each login failure. (Users can
initiate login retries by pressing the Return key.) This
parameter is intended to be used with the LGI_RETRY_LIM
parameter; it allows dialup users a reasonable amount of time
and number of opportunities to attempt logins before they lose
the carrier.
LGI_RETRY_TMO is a DYNAMIC parameter.
114 – LNMPHASHTBL
LNMPHASHTBL sets the size of the process logical name hash table.
Logical names are hashed using a function of the name length
and contents. The LNMPHASHTBL parameter determines the number
of entries for process-private logical names. The recommended
setting is the average number of process-private logical names.
Note that the hashed values are rounded up to the nearest power
of 2.
LNMPHASHTBL has the GEN attribute. On VAX systems, LNMPHASHTBL is
also an AUTOGEN-altered parameter.
115 – LNMSHASHTBL
LNMSHASHTBL sets the size of the system logical name hash table.
Logical names are hashed using a function of the name length
and contents. The LNMSHASHTBL parameter determines the number
of entries for shareable logical names. These names include all
names from the system, group, and job logical name tables. The
recommended setting allows one to four logical names per hash
table entry. The default setting is usually adequate, unless
your installation has a large number of groups, or many jobs are
active simultaneously. In that case, an increase in the value of
the next higher power of 2 might improve logical name translation
performance. Note that the hashed values are rounded up to the
nearest power of 2.
LNMSHASHTBL has the AUTOGEN, FEEDBACK, and GEN attributes.
116 – LOAD_PWD_POLICY
LOAD_PWD_POLICY controls whether the SET PASSWORD command
attempts to use site-specific password policy routines, which
are contained in the shareable image SYS$LIBRARY:VMS$PASSWORD_
POLICY.EXE. The default is 0, which indicates not to use policy
routines.
117 – LOAD_SYS_IMAGES
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
LOAD_SYS_IMAGES controls the loading of system images described
in the system image data file, VMS$SYSTEM_IMAGES. This parameter
is a bit mask.
On Alpha and Integrity servers, the following bits are defined:
Bit Description
0 (SGN$V_LOAD_SYS_IMAGES) Enables loading alternate execlets
specified in VMS$SYSTEM_IMAGES.DATA.
1 (SGN$V_EXEC_SLICING) Enables executive slicing.
2 (SGN$V_RELEASE_PFNS) Enables releasing unused portions of
the Alpha and Integrity servers huge
pages.
These bits are on by default. Using conversational bootstrap exec
slicing can be disabled.
On Alpha and Integrity servers, LOAD_SYS_IMAGES is an AUTOGEN
parameter.
118 – LOCKDIRWT
LOCKDIRWT determines the portion of lock manager directory that
this system handles. The default value is usually adequate.
LOCKDIRWT is an AUTOGEN parameter.
119 – LOCKIDTBL
LOCKIDTBL sets the initial number of entries in the system Lock
ID table and defines the amount by which the Lock ID table is
extended whenever the system runs out of locks. One entry must
exist for each lock in the system; each entry requires 4 bytes.
For simple timesharing systems, the default value is adequate.
If your application uses many locks, as in the case of heavy RMS
file sharing or a database management application, you should
increase this parameter. When you change the value of LOCKIDTBL,
examine the value of RESHASHTBL and change it if necessary.
The OpenVMS Lock Management facility is described in the VSI
OpenVMS Programming Concepts Manual. You can monitor locks with
the MONITOR LOCK command of the Monitor utility.
LOCKIDTBL has the AUTOGEN, FEEDBACK, and MAJOR attributes.
120 – LOCKIDTBL_MAX
LOCKIDTBL_MAX is obsolete beginning with OpenVMS Version 7.1.
121 – LOCKRETRY
LOCKRETRY establishes the number of attempts made to lock a
multiprocessor data structure.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
122 – LOCKRMWT
NOTE
On OpenVMS Version 8.3 systems, LOCKRMWT does not control
lock remastering. See LOCKDIRWT.
LOCKRMWT can have a value from zero to 10. The default is 5.
Remaster decisions are based on the difference in lock remaster
weights between the master and a remote node. When weights are
equal, the remote node needs about 13% more activity before the
tree is remastered. If a remote node has a higher lock remaster
weight, the amount of activity is less. If the remote node has a
lower lock remaster weight, the additional activity required to
move the tree is much greater.
Lock remaster weights of zero and 10 have additional meanings.
A value of zero indicates that a node does not want to master
trees and always remasters to an interested node with a higher
LOCKRMWT. Lock trees on an interested node with a LOCKRMWT
lower than 10 are remastered to the node with a weight of 10
for LOCKRMWT.
LOCKRMWT is a DYNAMIC parameter.
123 – LONGWAIT
LONGWAIT defines how much real time (in seconds) must elapse
before the swapper considers a process to be temporarily idle.
This parameter is applied to local event flag (LEF) and hibernate
(HIB) waits to detect such conditions as an inactive terminal or
ACP.
LONGWAIT has the DYNAMIC, GEN, and MAJOR attributes. On Alpha
and Integrity servers, LONGWAIT is also an AUTOGEN-altered
parameter.
124 – MAXBOBMEM
(Alpha and Integrity servers) MAXBOBMEM defines the maximum
amount of physical memory, measured in pagelets, that can be
associated with a single buffer object created by a process
in user mode. The default value of 0 means there is no system-
imposed limit on the size of a buffer object.
MAXBOBMEM is a DYNAMIC parameter.
Other MAXBOB* parameters are obsolete beginning with OpenVMS
Version 7.3.
125 – MAXBUF
MAXBUF sets the maximum allowable size for any single buffered
I/O packet. Buffered I/O packets are allocated from the
permanently resident nonpaged dynamic pool. The terminal,
mailbox, and printer device drivers are examples of device
drivers that perform buffered I/O.
The number of bytes specified in the I/O request plus the size of
a driver-dependent and function-dependent header area determine
the required buffered I/O packet size. The size of the header
area is a minimum of 16 bytes; there is no absolute upper limit.
However, this header area is usually a few hundred bytes in size.
The default value on Alpha and Integrity servers continues to be
8192.
The maximum value of MAXBUF is 64000 bytes.
MAXBUF is a DYNAMIC parameter.
126 – MAXCLASSPRI
If class scheduling is enabled, MAXCLASSPRI sets the maximum
range in the priority range of class-scheduled processes.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
MAXCLASSPRI is a DYNAMIC parameter.
127 – MAXPROCESSCNT
MAXPROCESSCNT sets the number of process entry slots allocated at
bootstrap time. One slot is required for each concurrent process
on the system. Each slot requires 6 bytes of permanently resident
memory.
The default value is normally configured to allow you to create
the desired number of processes. If the following message
appears, you need to increase the value of MAXPROCESSCNT:
%SYSTEM-F-NOSLOT, No PCB to create process
On Alpha and Integrity servers beginning with Version 8.1, the
default value is 32,767.
MAXPROCESSCNT has the AUTOGEN, FEEDBACK, GEN, and MAJOR
attributes.
128 – MAXQUEPRI
MAXQUEPRI determines the highest scheduling priority that can be
assigned to jobs entered in batch and output (printer, server,
and terminal) queues without the submitter process having OPER or
ALTPRI privilege. The value of this parameter can range from 0 to
255; the default is 100. The value of MAXQUEPRI should be greater
than or equal to DEFQUEPRI.
NOTE
MAXQUEPRI refers to relative queue scheduling priority, not
to the execution priority of the job.
MAXQUEPRI is a DYNAMIC parameter.
129 – MAXSYSGROUP
MAXSYSGROUP sets the highest value that a group number can have
and still be classified as a system UIC group number. Note that
the specification is not in octal unless preceded by the %O radix
indicator. This parameter is normally left at 8 (10 octal).
MAXSYSGROUP is a DYNAMIC parameter.
130 – MC_SERVICES_P0
(Alpha only) MC_SERVICES_P0 controls whether other MEMORY CHANNEL
nodes in the cluster continue to run if this node bugchecks or
shuts down.
A value of 1 causes other nodes in the MEMORY CHANNEL cluster to
crash with bugcheck code MC_FORCED_CRASH if this node bugchecks
or shuts down.
The default value is 0. A setting of 1 is intended only for
debugging purposes; the parameter should otherwise be left at
its default value.
MC_SERVICES_P0 is a DYNAMIC parameter.
131 – MC_SERVICES_P1
(Alpha only) This special parameter is reserved for VSI use. Its
value must be the same on all nodes connected by MEMORY CHANNEL.
MC_SERVICES_P1 is a DYNAMIC parameter.
132 – MC_SERVICES_P2
(Alpha only) MC_SERVICES_P2 specifies whether to load the
PMDRIVER (PMA0) MEMORY CHANNEL cluster port driver.
PMDRIVER is a driver that serves as the MEMORY CHANNEL cluster
port driver. It works together with MCDRIVER (the MEMORY CHANNEL
device driver and driver interface) to provide MEMORY CHANNEL
clustering. If PMDRIVER is not loaded, cluster connections are
not made over the MEMORY CHANNEL interconnect.
The default value is 1, which causes PMDRIVER to be loaded when
you boot the system. When you run CLUSTER_CONFIG.COM and select
the MEMORY CHANNEL option, PMDRIVER is loaded automatically when
you reboot the system.
VSI recommends that this value not be changed. This parameter
value must be the same on all nodes connected by MEMORY CHANNEL.
133 – MC_SERVICES_P3
(Alpha only) MC_SERVICES_P3 specifies the maximum number of tags
supported. The maximum value is 2048, and the minimum value is
100.
The default value is 800. VSI recommends that this value not
be changed. This parameter value must be the same on all nodes
connected by MEMORY CHANNEL.
MC_SERVICES_P3 is a DYNAMIC parameter.
134 – MC_SERVICES_P4
(Alpha only) MC_SERVICES_P4 specifies the maximum number of
regions supported. The maximum value is 4096, and the minimum
value is 100.
The default value is 200. VSI recommends that this value not
be changed. This parameter value must be the same on all nodes
connected by MEMORY CHANNEL.
135 – MC_SERVICES_P5
(Alpha only) MC_SERVICES_P5 is reserved for VSI use only and must
remain at the default value of 8000000. This value must be the
same on all nodes connected by MEMORY CHANNEL.
MC_SERVICES_P5 is a DYNAMIC parameter.
136 – MC_SERVICES_P6
(Alpha only) MC_SERVICES_P6 specifies MEMORY CHANNEL message
size, the body of an entry in a free queue, or a work queue. The
maximum value is 65536, and the minimum value is 544.
The default value is 992. This value is suitable in all cases
except for systems with highly constrained memory. For such
systems, you can reduce the memory consumptions of MEMORY CHANNEL
by slightly reducing the default value of 992. The value of MC_
SERVICES_P6 must always be equal to or greater than the result of
the following calculations:
1. Select the larger of SCS_MAXMSG and SCS_MAXDG.
2. Round that value up to the next quadword.
The value of MC_SERVICES_P6 must be the same on all nodes
connected by MEMORY CHANNEL.
137 – MC_SERVICES_P7
(Alpha only) MC_SERVICES_P7 specifies whether to suppress or
display messages about MEMORY CHANNEL activities on this node.
This parameter can be set to a value of 0, 1, or 2:
o A value of 0 indicates nonverbose mode: no informational
messages appear on the console or in the error log.
o A value of 1 indicates verbose mode: informational messages
from both MCDRIVER and PMDRIVER appear on the console and in
the error log.
o A value of 2 provides the same output as a value of 1, with
the addition of PMDRIVER stalling and recovery messages.
The default value is 0. VSI recommends that this value not
be changed except while debugging MEMORY CHANNEL problems or
adjusting the MC_SERVICES_P9 parameter.
MC_SERVICES_P7 is a DYNAMIC parameter.
138 – MC_SERVICES_P8
(Alpha only) MC_SERVICES_P8 is reserved for VSI use only and must
remain at the default value of 0. The value must be the same on
all nodes connected by MEMORY CHANNEL.
139 – MC_SERVICES_P9
(Alpha only) MC_SERVICES_P9 specifies the number of initial
entries in a single channel's free queue. The maximum value is
2048, and the minimum value is 10.
Note that MC_SERVICES_P9 is not a dynamic parameter; you must
reboot the system after each change for that change to take
effect.
The default value is 150. VSI recommends that this value not be
changed.
The value of MC_SERVICES_P9 must be the same on all nodes
connected by MEMORY CHANNEL.
140 – MINCLASSPRI
If class scheduling is enabled, MINCLASSPRI sets the minimum
range in the priority range of class-scheduled processes.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
MINCLASSPRI is a DYNAMIC parameter.
141 – MINWSCNT
The value specified by MINWSCNT is added to the size of the
process header to establish the minimum working set size.
On Alpha and Integrity servers, MINWSCNT sets the minimum number
of pages required for the execution of a process. The default
value is 20; the minimum value is 10.
MINWSCNT is an AUTOGEN parameter.
142 – MMG_CTLFLAGS
MMG_CTLFLAGS is a bitmask used to enable or disable memory
management-related activities.
The first two bits, 0 and 1, control the proactive memory
reclamation mechanisms. Bit 2 controls deferred memory testing.
The following bit mask values are defined:
Bit Description
0 If this bit is set, reclamation is enabled by trimming
from periodically executing, but otherwise idle,
processes. This occurs when the size of the free list
plus the modified list drops below two times the value of
FREEGOAL. This function is disabled if the bit is clear.
1 If this bit is set, reclamation is enabled by outswapping
processes that have been idle for longer than LONGWAIT
seconds. This occurs when the size of the free list drops
below FREEGOAL. This function is disabled if the bit is
clear.
2 Controls deferred memory testing (only on AlphaServer
4100 systems). You can use this bit to speed up elapsed
bootstrap time by controlling when memory is tested:
o If the bit is clear (the default), OpenVMS tests memory
as a background activity, which might or might not
complete before the end of the bootstrap process.
o If the bit is set, all memory is tested in the
bootstrap process by the end of the EXEC_INIT phase
(that is, before IPL is lowered from 31).
3 Reserved to OpenVMS use; must be zero.
4 If this bit is clear (the default), all page sizes
supported by hardware can be used to map resident memory
sections on Integrity servers. If this bit is set, page
sizes on Integrity servers are limited to the maximum
GH factor available on Alpha systems (512 * <system page
size>).
5-7 Reserved for future use.
MMG_CTLFLAGS is an AUTOGEN and DYNAMIC parameter.
143 – MOUNTMSG_(D)
MOUNTMSG controls whether or not the messages that log volume
mounts appear on the operator's terminal and in the operator's
log. The default value of 0 disables reporting of these messages.
This parameter does not control the messages generated by mount
assistance requests.
MOUNTMSG is a DYNAMIC parameter.
144 – MPDEV_AFB_INTVL
(Alpha and Integrity servers) MPDEV_AFB_INTVL specifies the
automatic failback interval in seconds. The automatic failback
interval is the minimum number of seconds that must elapse before
the system attempts another failback from an MSCP path to a
direct path on the same device.
MPDEV_POLLER must be set to ON to enable automatic failback. You
can disable automatic failback without disabling the poller by
setting MPDEV_AFB_INTVL to 0. The default is 300 seconds.
145 – MPDEV_D*
(Alpha and Integrity servers) MPDEV_D1 through MPDEV_D4 are
reserved for use by the operating system.
146 – MPDEV_ENABLE
(Alpha and Integrity servers) MPDEV_ENABLE enables the formation
of multipath sets when set to ON (1). If MPDEV_ENABLE is set
to OFF (0), the formation of additional multipath sets and the
addition of new paths to existing multipath sets are disabled.
However, existing multipath sets remain in effect. The default is
ON.
MPDEV_REMOTE and MPDEV_AFB_INTVL have no effect when MPDEV_ENABLE
is set to OFF.
147 – MPDEV_LCRETRIES
(Alpha and Integrity servers) MPDEV_LCRETRIES controls the number
of times the system retries the direct paths to the controller
that the logical unit is online to, before moving on to direct
paths to the other controller, or to an MSCP served path to the
device. The valid range for retries is 1 through 256. The default
is 1.
148 – MPDEV_POLLER
(Alpha and Integrity servers) MPDEV_POLLER enables polling of
the paths to multipath set members when set to ON (1). Polling
allows early detection of errors on inactive paths. If a path
becomes unavailable or returns to service, the system manager is
notified with an OPCOM message. When set to OFF (0), multipath
polling is disabled. The default is ON. Note that this parameter
must be set to ON to use the automatic failback feature.
149 – MPDEV_REMOTE
(Alpha and Integrity servers) MPDEV_REMOTE enables MSCP served
paths to become members of a multipath set when set to ON (1).
When set to OFF (0), only local paths to a SCSI or Fibre Channel
device is used in the formation of additional multipath sets.
However, setting this parameter to OFF does not have any effect
on existing multipath sets that have remote paths.
To use multipath failover to a served path, MPDEV_REMOTE must
be enabled on all systems that have direct access to shared
SCSI/Fibre Channel devices. The first release to provide this
feature is OpenVMS Alpha Version 7.3-1. Therefore, all nodes
on which MPDEV_REMOTE is enabled must be running OpenVMS Alpha
Version 7.3-1 (or later).
If MPDEV_ENABLE is set to OFF (0), the setting of MPDEV_REMOTE
has no effect because the addition of all new paths to multipath
sets is disabled. The default is ON.
150 – MPW_HILIMIT
MPW_HILIMIT sets an upper limit for the modified-page list. When
the list accumulates the number of pages specified by this limit,
writing of the list begins. The pages that are written are then
transferred to the free-page list.
If MPW_HILIMIT is too low, excessive page faulting can occur from
the page file. If it is too high, too many physical pages can be
consumed by the modified-page list.
If you increase MPW_HILIMIT, you might also need to increase
MPW_WAITLIMIT. Note that if MPW_WAITLIMIT is less than
MPW_HILIMIT, a system deadlock occurs. The values for the two
parameters are usually equal.
MPW_HILIMIT has the AUTOGEN and GEN attributes.
151 – MPW_IOLIMIT
MPW_IOLIMIT specifies the number of outstanding I/Os to the
modified-page writer.
On Alpha and Integrity servers, MPW_IOLIMIT is an AUTOGEN-altered
parameter.
152 – MPW_LOLIMIT
MPW_LOLIMIT sets a lower limit for the modified-page list. When
writing of the list causes the number of pages on the list to
drop to or below this limit, writing stops.
MPW_LOLIMIT ensures that a certain number of pages are available
on the modified-page list for page faults. If the number is
too small, the caching effectiveness of the modified-page list
is reduced. If it is too high, less memory is available for
processes, so that swap (and page) may increase.
MPW_LOLIMIT has the AUTOGEN and GEN attributes.
153 – MPW_LOWAITLIMIT
MPW_LOWAITLIMIT specifies the threshold at which processes in
the miscellaneous wait state MPWBUSY are allowed to resume.
MPW_LOWAITLIMIT increases system performance for fast processors
with large memories by reducing the amount of time processes
spend in the MPWBUSY wait state.
MPW_LOWAITLIMIT has the AUTOGEN and DYNAMIC attributes.
154 – MPW_PRIO
MPW_PRIO sets the priority of I/O transfers initiated by the
modified page writer. The maximum value is 31, the minimum is 0,
and the default is 4.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
155 – MPW_THRESH
MPW_THRESH sets a lower bound of pages that must exist on the
modified-page list before the swapper writes this list to acquire
free pages. If this requirement is met, the swapper tries to
write the modified-page list rather than taking pages away from
or swapping out a process.
MPW_THRESH has the DYNAMIC attribute. On Alpha and Integrity
servers, MPW_THRESH is also an AUTOGEN parameter.
156 – MPW_WAITLIMIT
MPW_WAITLIMIT sets the number of pages on the modified-page list
that causes a process to wait until the next time the modified-
page writer writes the modified list. This parameter limits the
rate at which any single process can produce modified pages. If
this value is less than MPW_HILIMIT, a system deadlock occurs.
The value for this parameter is normally equal to MPW_HILIMIT.
MPW_WAITLIMIT has the AUTOGEN and DYNAMIC attributes.
157 – MPW_WRTCLUSTER
MPW_WRTCLUSTER sets the number of pages to be written during one
I/O operation from the modified-page list to the page file or
a section file. The actual size of the cluster may be limited
by the number of pages available for the I/O operation. This
parameter can range in value from 16 to 120, in multiples of 8.
Each page in the cluster requires 6 bytes of permanently resident
memory.
If MPW_WRTCLUSTER is too small, it takes many I/O operations
to empty the modified-page list. If MPW_WRTCLUSTER is too large
for the speed of the disk that holds the page file, other I/O
operations are held up for the modified-page list write.
On Alpha and Integrity servers, the MPW_WRTCLUSTER default value
is 64 8192-byte pages; its maximum value is 512 8192-byte pages;
and its minimum value is 16 8192-byte pages.
MPW_WRTCLUSTER has the AUTOGEN and GEN attributes.
158 – MSCP_BUFFER
This buffer area is the space used by the server to transfer data
between client systems and local disks.
On Alpha and Integrity servers, MSCP_BUFFER specifies the number
of pagelets to be allocated to the MSCP server's local buffer
area.
MSCP_BUFFER is an AUTOGEN and FEEDBACK parameter.
159 – MSCP_CMD_TMO
MSCP_CMD_TMO is the time in seconds that the OpenVMS MSCP server
uses to detect MSCP command timeouts. The MSCP Server must
complete the command within a built-in time of approximately
40 seconds plus the value of the MSCP_CMD_TMO parameter.
The MSCP_CMD_TMO default value of 0 is normally adequate. A
value of 0 provides the same behavior as in previous releases
of OpenVMS (which did not have an MSCP_CMD_TMO system parameter).
A nonzero setting increases the amount of time before an MSCP
command times out.
If command timeout errors are being logged on client nodes,
setting the parameter to a nonzero value on OpenVMS servers
may reduce the number of errors logged. As the value of the
MSCP_CMD_TMO increases, the number of client MSCP command timeouts
will decrease, at the cost of increased time to detect a faulty
MSCP controller or MSCP-served device.
If you need to decrease the number of command timeout errors, VSI
recommends that you set an initial value of 60. If timeout errors
continue to be logged, you can increase this value in increments
of 20 seconds.
MSCP_CMD_TMO is a DYNAMIC parameter.
160 – MSCP_CREDITS
MSCP_CREDITS specifies the number of outstanding I/O requests
that can be active from one client system.
The default value is currently 32. Unless a system has very
constrained memory available, VSI recommends that these values
not be increased.
161 – MSCP_LOAD
MSCP_LOAD controls the loading of the MSCP server during a system
boot. Specify one of the following values:
Value Description
0 Do not load the MSCP server. This is the default value.
1 Load the MSCP server and serve disks as specified by the
MSCP_SERVE_ALL parameter.
MSCP_LOAD has the AUTOGEN attribute.
162 – MSCP_SERVE_ALL
MSCP_SERVE_ALL is a bit mask that controls disk serving in an
OpenVMS Cluster. A disk is served regardless of its allocation
class unless bit 3 has a value of 1.
Starting with OpenVMS Version 7.2, the serving types are
implemented as a bit mask. To specify the type of serving your
system will perform, locate the type you want in the following
table and specify its value. For some systems, you may want to
specify two serving types, such as serving the system disk and
serving locally attached disks. To specify such a combination,
add the values of each type, and specify the sum.
In a mixed-version cluster that includes any systems running
OpenVMS Version 7.1-x or earlier, serving all available disks
is restricted to serving all disks except those whose allocation
class does not match the system's node allocation class (prior
to Version 7.2). To specify this type of serving, use the value 9
(which sets bit 0 and bit 3).
The following table describes the serving type controlled by each
bit and its decimal value:
Bit and
Value
When Set Description
Bit 0 (1) Serve all available disks (locally attached and
those connected to HSx and DSSI controllers).
Disks with allocation classes that differ from
the system's allocation class (set by the ALLOCLASS
parameter) are also served if bit 3 is not set.
Bit 1 (2) Serve locally attached (non-HSx and DSSI) disks.
Bit 2 (4) Serve the system disk. This is the default setting.
This setting is important when other nodes in the
cluster rely on this system being able to serve
its system disk. This setting prevents obscure
contention problems that can occur when a system
attempts to complete I/O to a remote system disk
whose system has failed.
Bit 3 (8) Restrict the serving specified by bit 0. All disks
except those with allocation classes that differ
from the system's allocation class (set by the
ALLOCLASS parameter) are served.
This is pre-Version 7.2 behavior. If your cluster
includes systems running OpenVMS 7.1-x or earlier,
and you want to serve all available disks, you must
specify 9, the result of setting this bit and bit
0.
Although the serving types are now implemented as a bit mask, the
values of 0, 1, and 2, specified by bit 0 and bit 1, retain their
original meanings:
0 - Do not serve any disks (the default for earlier versions
of OpenVMS).
1 - Serve all available disks.
2 - Serve only locally attached (non-HSx and non-DSSI) disks.
If the MSCP_LOAD system parameter is 0, MSCP_SERVE_ALL is
ignored.
163 – MULTIPROCESSING
MULTIPROCESSING controls the loading of the system
synchronization image.
Specify one of the following values:
Value Description
0 Load the uniprocessing synchronization image
SYSTEM_SYNCHRONIZATION_UNI.EXE.
1 If the CPU type is capable of SMP and two or
more CPUs are present on the system, load the
full-checking multiprocessing synchronization
image SYSTEM_SYNCHRONIZATION.EXE. Otherwise,
load the uniprocessing synchronization image
SYSTEM_SYNCHRONIZATION_UNI.EXE.
2 Always load the full-checking version
SYSTEM_SYNCHRONIZATION.EXE, regardless of system
configuration or CPU availability.
3 If the CPU type is capable of SMP and two or more
CPUs are present on the system, load the optimized
streamlined multiprocessing image:
o On Alpha and Integrity servers, this image is
SYSTEM_SYNCHRONIZATION_MIN.EXE.
Otherwise, load the uniprocessing synchronization image
SYSTEM_SYNCHRONIZATION_UNI.EXE. The default value is 3.
4 Always load the streamlined multiprocessing image
SYSTEM_SYNCHRONIZATION_MIN.EXE, regardless of system
configuration or CPU availability.
Setting the SYSTEM_CHECK parameter to 1 has the effect of setting
MULTIPROCESSING to 2.
164 – MULTITHREAD
MULTITHREAD controls the availability of kernel threads
functions. Specify one of the following values:
Value Description
0 Both Thread Manager upcalls and the creation of
multiple kernel threads are disabled.
1 Thread Manager upcalls are enabled; the creation
of multiple kernel threads is disabled.
2-256 (Alpha Both Thread Manager upcalls and the creation
and Integrity of multiple kernel threads are enabled. The
servers) number specified represents the maximum number
of kernel threads that can be created for a
single process.
The maximum value for MULTITHREAD is 256.
MULTITHREAD is an AUTOGEN and DYNAMIC parameter.
165 – MVSUPMSG_INTVL
(Alpha and Integrity servers) The system suppresses mount
verification start and end messages for fibre channel disk
devices if mount verification completes on the first attempt
and if mount verification does not occur too often. MVSUPMSG_NUM
and this parameter establish this limit.
The system issues a mount verification message after a sequence
of MVSUPMSG_NUM mount verifications have gone unannounced on a
specific fibre channel disk device within a span of MVSUPMSG_
INTVL seconds.
If this parameter is zero, all mount verification messages are
announced.
MVSUPMSG_INTVL is a DYNAMIC parameter.
166 – MVSUPMSG_NUM
(Alpha and Integrity servers) The system suppresses mount
verification start and end messages for fibre channel disk
devices if mount verification completes on the first attempt and
if mount verification does not occur too often. MVSUPMSG_INTVL
and this parameter establish this limit.
The system issues a mount verification message after a sequence
of MVSUPMSG_NUM mount verifications have gone unannounced on a
specific fibre channel disk device within a span of MVSUPMSG_
INTVL seconds.
If this parameter is zero, all mount verification messages are
announced.
MVSUPMSG_NUM is a DYNAMIC parameter.
167 – MVTIMEOUT
MVTIMEOUT is the time in seconds that a mount verification
attempt continues on a given disk volume. If the mount
verification does not recover the volume within that time, the
I/O operations outstanding to the volume terminate abnormally.
MVTIMEOUT is a DYNAMIC parameter. On Alpha and Integrity servers,
MVTIMEOUT is also an AUTOGEN parameter.
168 – NET_CALLOUTS
NET_CALLOUTS is normally set to 0. A value of 255 indicates that
no attempt is to be made to assign a new proxy connection to an
active server, but that a new process must be started to invoke
the installation security policy callout modules in LOGINOUT.EXE.
Values 1 through 254 are reserved for future use.
NET_CALLOUTS is a DYNAMIC parameter.
169 – NISCS_CONV_BOOT
NISCS_CONV_BOOT controls whether a conversational boot is
permitted during a remote system boot. The default value of 0
specifies that conversational boots are not permitted.
170 – NISCS_LOAD_PEA0
NISCS_LOAD_PEA0 controls whether the NI-SCS port driver PEDRIVER
is loaded during system boot. The default of 0 specifies that the
PEDRIVER is not loaded.
171 – NISCS_MAX_PKTSZ
This parameter specifies an upper limit on the size, in bytes,
of the user data area in the largest packet sent by NISCA on any
local area network (LAN).
NISCS_MAX_PKTSZ allows the system manager to change the packet
size used for cluster communications on network communication
paths. PEDRIVER automatically allocates memory to support
the largest packet size that is usable by any virtual circuit
connected to the system up to the limit set by this parameter. On
Alpha and Integrity servers, to optimize performance, the default
value is the largest packet size currently supported by OpenVMS.
PEDRIVER uses NISCS_MAX_PKTSZ to compute the maximum amount of
data to transmit in any LAN packet:
LAN packet size <= LAN header (padded Ethernet format)
+ NISCS_MAX_PKTSZ
+ NISCS checksum (only if data checking
is enabled)
+ LAN CRC or FCS
The actual packet size automatically used by PEDRIVER might be
smaller than the NISCS_MAX_PKTSZ limit for any of the following
reasons:
o On a per-LAN path basis, if PEdriver determines that the LAN
path between two nodes, including the local and remote LAN
adapters and intervening LAN equipment, can only convey a
lesser size.
In other words, only nodes with large-packet LAN adapters
connected end-to-end by large-packet LAN equipment can use
large packets. Nodes connected to large-packet LANs but having
an end-to-end path that involves an Ethernet segment restrict
packet size to that of an Ethernet packet (1498 bytes).
o For performance reasons, PEDRIVER might further limit
the upper bound on packet size so that the packets can be
allocated from a lookaside list in the nonpaged pool.
The actual memory allocation includes the required data structure
overhead used by PEDRIVER and the LAN drivers, in addition to the
actual LAN packet size.
The following table shows the minimum NISCS_MAX_PKTSZ value
required to use the maximum packet size supported by specified
LAN types:
Type of LAN Minimum Value for NISCS_MAX_PKTSZ
Ethernet 1498
FDDI 4382 (before Version 7.3)
4396 (Version 7.3 and later)
Gigabit Ethernet 8192
ATM 7606
Note that the maximum packet size for some Gigabit Ethernet
adapters is larger than the maximum value of NISCS_MAX_PKTSZ
(8192 bytes). See the LAN_FLAGS parameter for a description of
how to enable jumbo frames on Gigabit Ethernet-that is, packet
sizes larger than those noted for Ethernet.
On Alpha and Integrity servers, NISCS_MAX_PKTSZ is an AUTOGEN
parameter.
172 – NISCS_PORT_SERV
NISCS_PORT_SERV provides flag bits for PEDRIVER port services:
o Setting bits 0 and 1 (hex bitmask value 3) enables data
checking.
o Setting bit 2 (hex bitmask value 4) enables data compression
on all virtual channels (VCs) to nodes that support
compression.
The remaining bits are reserved for future use.
Starting with OpenVMS Version 7.3-1, you can use the SCACP
command SET VC/CHECKSUMMING to specify data checking on the VCs
to certain nodes. You can do this on a running system. (For more
information, see the SCACP documentation in the VSI OpenVMS System
Management Utilities Reference Manual.
Starting with OpenVMS Version 8.3, you can also use the SCACP
command SET VC/COMPRESSION to specify data compression on the
on the VCs to certain nodes. You can use SCACP to enable either
data checking or data compression on a running system. (See the
SCACP documentation in the the VSI OpenVMS System Management
Utilities Reference Manual for more information. Also starting
with OpenVMS Version 8.3, the NISCS_PORT_SERV system parameter
is dynamic, that is, changing the setting of this parameter no
longer requires a reboot. Furthermore, this parameter applies
to all virtual circuits between the node on which it is set and
other nodes in the cluster.
NISCS_PORT_SERV has the DYNAMIC and AUTOGEN attributes.
173 – NOAUTOCONFIG
NOAUTOCONFIG controls whether all devices are automatically
configured when the system boots. The default value of 0 sets the
system to automatically configure all devices. Set NOAUTOCONFIG
to 1 (no automatic configuration) only for debugging purposes.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
NOAUTOCONFIG is a DYNAMIC parameter.
174 – NOCLUSTER
NOCLUSTER controls whether page read clustering is inhibited
when the system boots. Set NOCLUSTER to 1 (inhibit page read
clustering) only for debugging purposes.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
175 – NOPGFLSWP
If enabled, NOPGFLSWP disables swapping into page files.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
176 – NPAGECALC
NPAGECALC controls whether the system automatically calculates
the initial size for nonpaged dynamic memory.
VSI sets the default value of NPAGECALC to 1 only during the
initial boot after an installation or upgrade. When the value
of NPAGECALC is 1, the system calculates an initial value for the
NPAGEVIR and NPAGEDYN system parameters. This calculated value is
based on the amount of physical memory in the system.
NPAGECALC's calculations do not reduce the values of NPAGEVIR and
NPAGEDYN from the values you see or set at the SYSBOOT prompt.
However, NPAGECALC's calculation might increase these values.
AUTOGEN sets NPAGECALC to 0. NPAGECALC should always remain 0
after AUTOGEN has determined more refined values for the NPAGEDYN
and NPAGEVIR system parameters.
177 – NPAGEDYN
NPAGEDYN sets the size of the nonpaged dynamic pool in bytes.
This figure is rounded down to an integral number of pages.
NPAGEDYN establishes the initial setting of the nonpaged pool
size, but the pool size can be increased dynamically.
To set a value for this parameter, use AUTOGEN initially, and
then monitor the amount of space actually used with the DCL
command SHOW MEMORY/POOL/FULL.
For the benefit of OpenVMS VAX systems with limited physical
memory, AUTOGEN logs a warning message in its report if NPAGEDYN
exceeds 10 percent of physical memory or if NPAGEVIR exceeds 33
percent of physical memory.
AUTOGEN also limits its own calculated value for NPAGEDYN to
20 percent of physical memory and limits NPAGEVIR to 50 percent
of physical memory. These calculated values are adequate for
most workstations and systems with 16 or fewer megabytes of
physical memory. If your system requires a larger value, you can
override the AUTOGEN calculated values by setting higher values
in MODPARAMS.DAT.
NPAGEDYN has AUTOGEN, FEEDBACK, GEN, and MAJOR attributes.
178 – NPAGERAD
(Alpha and Integrity servers) NPAGERAD specifies the total number
of bytes of nonpaged pool that will be allocated for Resource
Affinity Domains (RADs) other than the base RAD. For platforms
that have no RADs, NPAGERAD is ignored. Notice that NPAGEDYN
specifies the total amount of nonpaged pool for all RADs.
Also notice that the OpenVMS system might round the specified
values higher to an even number of pages for each RAD, which
prevents the base RAD from having too little nonpaged pool. For
example, if the hardware is an AlphaServer GS160 with 4 RADs:
NPAGEDYN = 6291456 bytes
NPAGERAD = 2097152 bytes
In this case, the OpenVMS system allocates a total of
approximately 6,291,456 bytes of nonpaged pool. Of this amount,
the system divides 2,097,152 bytes among the RADs that are not
the base RAD. The system then assigns the remaining 4,194,304
bytes to the base RAD.
NOTE
The system actually rounds up to an even number of pages
on each RAD. In addition, the base RAD is never assigned a
value less than the smaller of the value of NPAGEDYN and 4
megabytes.
On AlphaServer GS series processors on OpenVMS systems prior to
Version 7.3-1, system managers frequently saw pool expansion that
increasing NPAGEDYN did not reduce. This problem was caused by
leaving NPAGERAD at its default value of 0.
Starting with OpenVMS Version 7.3-1, when NPAGERAD is 0 (the
default), the system calculates a value to use for NPAGERAD with
the following formula:
Base RAD memory
NPAGEDYN * (1- --------------- )
Total memory
This calculation gives more pool to the non-base RADs than before
and, therefore, reduces the expansion of non-base RADs.
NPAGERAD has the GEN attribute.
179 – NPAGEVIR
NPAGEVIR defines the maximum size to which NPAGEDYN can be
increased. If this value is too small, the system can hang.
If NPAGEVIR is too large, the result is a penalty of 4 bytes
per extra page on VAX and 8 bytes per extra page on Alpha and
Integrity servers.
For the benefit of OpenVMS VAX systems with limited physical
memory, AUTOGEN logs a warning message in its report if NPAGEDYN
exceeds 10 percent of physical memory or if NPAGEVIR exceeds 33
percent of physical memory.
AUTOGEN also limits its own calculated value for NPAGEDYN to 20
percent of physical memory, and limits NPAGEVIR to 50 percent
of physical memory. These calculated values are adequate for
most workstations and systems with 16 or fewer megabytes of
physical memory. If your system requires a larger value, you can
override the AUTOGEN calculated values by setting higher values
in MODPARAMS.DAT.
NPAGEVIR has AUTOGEN and GEN attributes.
180 – NPAG_AGGRESSIVE
Beginning with OpenVMS Version 8.2, the default values of NPAG_
AGGRESSIVE and NPAG_GENTLE are 100. A value of 100 turns off
both gentle and aggressive reclamation of nonpaged pool lookaside
lists. In many cases, when pool reclamation moves small packets
from the lookaside lists back to the variable list, the result
is fragmentation of the variable list. This fragmentation appears
as many small packets at the front of the variable list and a few
large packets at the end of the list.
When an allocation occurs for a packet that is larger than any
of the lookaside lists, the system must find a large enough
packet on the variable list. When heavily fragmented, the entire
variable list often must be searched to find a large enough
packet. Because the variable list is kept in address order, when
a large packet is deallocated, the entire list must be searched
again to deallocate the packet.
Under these conditions, system performance can be severely
degraded. For this reason, VSI recommends that you turn off pool
reclamation but keep both NPAG_AGGRESSIVE and NPAG_GENTLE system
parameters set to 100.
NPAG_AGGRESSIVE is a DYNAMIC parameter.
181 – NPAG_BAP_MAX
(Alpha and Integrity servers) NPAG_BAP_MAX is the size in bytes
of the bus addressable pool (BAP) that the system creates under
normal circumstances.
See also NPAG_BAP_MIN.
182 – NPAG_BAP_MAX_PA
(Alpha and Integrity servers) NPAG_BAP_MAX_PA is the highest
physical address in megabytes that is allowed in bus addressable
pool (BAP).
183 – NPAG_BAP_MIN
(Alpha and Integrity servers) NPAG_BAP_MIN is the size in bytes
of the bus addressable pool (BAP) that the system creates when
memory resources are unusually constrained.
184 – NPAG_BAP_MIN_PA
(Alpha and Integrity servers) NPAG_BAP_MIN_PA specifies the
lowest physical address in megabytes that is allowed in bus
addressable pool (BAP).
185 – NPAG_GENTLE
Beginning with Version 8.2, the default values of NPAG_AGGRESSIVE
and NPAG_GENTLE are 100. A value of 100 turns off both gentle
and aggressive reclamation of nonpaged pool lookaside lists.
In many cases, when pool reclamation moves small packets from
the lookaside lists back to the variable list, the result is
fragmentation of the variable list. This fragmentation appears
as many small packets at the front of the variable list and a few
large packets at the end of the list.
When an allocation occurs for a packet that is larger than any
of the lookaside lists, the system must find a large enough
packet on the variable list. When heavily fragmented, the entire
variable list often must be searched to find a large enough
packet. Because the variable list is kept in address order, when
a large packet is deallocated, the entire list must be searched
again to deallocate the packet.
Under these conditions, system performance can be severely
degraded. For this reason, VSI recommends that you turn off pool
reclamation but keep both NPAG_AGGRESSIVE and NPAG_GENTLE system
parameters set to 100.
NPAG_GENTLE is a DYNAMIC parameter.
186 – NPAG_INTERVAL
NPAG_INTERVAL is the number of seconds between passes of
nonpaged-pool gentle reclamation.
NPAG_INTERVAL is a DYNAMIC parameter.
187 – NPAG_RING_SIZE
NPAG_RING_SIZE represents the number of entries in the ring
buffer.
188 – PAGED_LAL_SIZE
PAGED_LAL_SIZE sets the maximum size, in bytes, to use for the
page dynamic pool lookaside lists. Use of these lookaside lists
can reduce paged dynamic pool variable freelist fragmentation and
improve paged pool allocation and deallocation performance.
By default, PAGED_LAL_SIZE is set to 0, which disables the use of
the paged dynamic pool lookaside lists.
For environments experiencing paged pool variable freelist
fragmentation a modest PAGED_LAL_SIZE, 512, has been adequate
to improve paged pool performance and reduce fragmentation. If
this parameter is made large and later decreased in size, some
paged pool packets can be left unused until the parameter is made
larger again, or the lookaside lists are reclaimed from due to a
paged pool shortage. The paged dynamic pool lookaside lists will
not occupy more than three-quarters of the available paged pool.
PAGED_LAL_SIZE has DYNAMIC, GEN, and MAJOR attributes.
189 – PAGFILCNT
On Alpha and Integrity servers, beginning in OpenVMS Version 7.3,
this parameter is obsolete.
PAGFILCNT has the GEN attribute on VAX systems.
190 – PAGTBLPFC
PAGTBLPFC specifies (in pages) the maximum number of page tables
to read to satisfy a fault for a nonresident page table.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
191 – PAMAXPORT
PAMAXPORT specifies the maximum port number to be polled on each
CI and DSSI. The CI and DSSI port drivers poll to discover newly
initialized ports or the absence/failure of previously responding
remote ports.
A system does not detect the existence of ports whose port
numbers are higher than this parameter's value. Thus, set this
parameter to a value that is equal to or greater than the highest
port number being used on any CI or DSSI connected to the system.
You can decrease this parameter to reduce polling activity if
the hardware configuration has fewer than 16 ports. For example,
if the CI or DSSI with the largest configuration has a total
of 5 ports assigned to port numbers 0 through 4, you could set
PAMAXPORT to 4.
If CI or DSSI devices are not configured on your system, this
parameter is ignored.
The default for this parameter is 15 (poll for all possible ports
0 through 15). VSI recommends that you set this parameter to the
same value on each cluster computer.
PAMAXPORT is a DYNAMIC parameter.
192 – PANOPOLL
Disables CI and DSSI polling for ports if set to 1. (The default
is 0.) When PANOPOLL is set, a computer does not discover that
another computer has shut down or powered down promptly and does
not discover a new computer that has booted. This parameter is
useful when you want to bring up a computer detached from the
rest of the cluster for checkout purposes.
PANOPOLL is functionally equivalent to uncabling the system from
the DSSI or star coupler. This parameter does not affect OpenVMS
Cluster communications by LAN.
The default value of 0 is the normal setting and is required
if you are booting from an HSC controller or if your system is
joining an OpenVMS Cluster. This parameter is ignored if no CI or
DSSI devices are configured on your system.
PANOPOLL is a DYNAMIC parameter.
193 – PANUMPOLL
PANUMPOLL establishes the number of CI and DSSI ports to be
polled each polling interval. The normal setting for PANUMPOLL
is 16.
On systems with less powerful CPUs, the parameter may be useful
in applications sensitive to the amount of contiguous time that
the system spends at IPL 8. Reducing PANUMPOLL reduces the amount
of time spent at IPL 8 during each polling interval, while
increasing the number of polling intervals needed to discover
new or failed ports.
If CI or DSSI devices are not configured on your system, this
parameter is ignored.
PANUMPOLL is a DYNAMIC parameter.
194 – PAPOLLINTERVAL
Specifies, in seconds, the polling interval the CI port driver
uses to poll for a newly booted computer, a broken port-to-port
virtual circuit, or a failed remote computer.
This parameter trades polling overhead against quick response to
virtual circuit failures. VSI recommends that you use the default
value for this parameter.
VSI recommends that you set this parameter to the same value on
each cluster computer.
PAPOLLINTERVAL is a DYNAMIC parameter.
195 – PAPOOLINTERVAL
Specifies, in seconds, the interval at which the port driver
checks available nonpaged pool after a pool allocation failure.
This parameter trades faster response to pool allocation failures
against increased polling overhead. VSI recommends that you use
the default value for this parameter.
If CI or DSSI devices are not configured on your system, this
parameter is ignored.
PAPOOLLINTERVAL is a DYNAMIC parameter.
196 – PASANITY
PASANITY controls whether the CI and DSSI port sanity timers are
enabled to permit remote systems to detect a system that has been
hung at IPL 8 or above for 100 seconds. It also controls whether
virtual circuit checking gets enabled on the local system. The
TIMVCFAIL parameter controls the time (1-99 seconds).
PASANITY is normally set to 1 and should be set to 0 only when
you are debugging with XDELTA or planning to halt the CPU for
periods of 100 seconds or more.
PASANITY is only semidynamic. A new value of PASANITY takes
effect on the next CI or DSSI port reinitialization.
If CI or DSSI devices are not configured on your system, this
parameter is ignored.
197 – PASTDGBUF
The number of datagram receive buffers to queue initially for the
cluster port driver's configuration poller. The initial value is
expanded during system operation, if needed.
Memory Channel devices ignore this parameter.
PASTDGBUF is an AUTOGEN parameter.
198 – PASTIMOUT
The basic interval at which the CI port driver wakes up to
perform time-based bookkeeping operations. It is also the period
after which a timeout is declared if no response to a start
handshake datagram has been received.
If CI or DSSI devices are not configured on your system, this
parameter is ignored.
The default value should always be adequate.
PASTIMOUT is a DYNAMIC parameter.
199 – PE1-6
PE1, PE2, PE3, PE4, PE5, PE6 are reserved for VSI use only. These
parameters are for cluster algorithms and their usages can change
from release to release. VSI recommends using the default values
for these special parameters.
200 – PFCDEFAULT
On Alpha and Integrity servers during execution of programs,
PFCDEFAULT controls the number of image pagelets read from
disk per I/O operation when a page fault occurs. The PFCDEFAULT
maximum default value is 2032 512-byte pagelets (127 8192-byte
Alpha and Integrity server pages).
The read I/O operations can take place from an image file or
from the page file. The actual size of the cluster can be less
than PFCDEFAULT, depending on the size of image sections and the
pattern of page references.
The value should not be greater than one-fourth the default size
of the average working set to prevent a single page fault from
displacing a major portion of a working set. Too large a value
for PFCDEFAULT can hurt system performance. PFCDEFAULT can be
overridden on an image-by-image basis with the CLUSTER option of
the OpenVMS linker.
PFCDEFAULT has the AUTOGEN and DYNAMIC attributes.
201 – PFN_COLOR_COUNT
(Alpha and Integrity servers) PFN_COLOR_COUNT specifies the
number of buckets (colors) into which all members of the zeroed
page list and all unencumbered members of the free page list are
sorted. OpenVMS Alpha systems might derive a preferred page color
from a request to map a given virtual page and attempt to map
that virtual page to a PFN of matching "color." This results in
less variance in which cache blocks are used when accessing that
page. This might or might not improve performance, depending on
the application.
This special parameter is use by VSI and is subject to change.
Do not change this parameter unless VSI recommends that you do so.
If you increase this parameter, you must also increase the ZERO_
LIST_HI system parameter.
202 – PFRATH
PFRATH specifies the page fault rate above which the limit of
a working set is automatically increased. The unit of measure
is the number of faults per 10 seconds of processor time. At a
setting of 120, for example, the system automatically increases
the limit of a working set if it is faulting more than 120 pages
per 10 seconds. Decreasing the value of this parameter tends to
increase the limits of the working sets, while increasing its
value tends to decrease their limits.
On Alpha and Integrity servers, the default value is 8 page
faults every 10 seconds.
PFRATH has the DYNAMIC and MAJOR attributes. On Alpha and
Integrity servers, PFRATH also is an AUTOGEN-altered parameter.
203 – PFRATL
PFRATL specifies the page fault rate below which the limit of
a working set is automatically decreased. The unit of measure
is the number of faults per 10 seconds of processor time. At a
setting of 1, for example, the system automatically decreases the
limit of a working set if it is faulting less than 1 page every
10 seconds.
Increasing the value of this parameter tends to decrease the
limits of the working sets, while decreasing its value tends to
increase their limits.
PFRATL has the AUTOGEN, DYNAMIC, and MAJOR attributes.
204 – PHYSICAL_MEMORY
(Alpha and Integrity servers) PHYSICAL_MEMORY specifies the
amount of physical memory available for use. The default setting
is -1, which equates to all memory in the system. Decreasing this
parameter allows you to test smaller configurations of memory
without having to remove memory boards.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
Because of hardware configuration requirements on the AlphaServer
ES47/ES80/GS1280 systems, VSI does not recommend altering the
setting of the system parameter PHYSICAL_MEMORY from its default
setting of -1. Artificially reducing the amount of memory can
produce unpredictable results on these systems.
PHYSICAL_MEMORY is an AUTOGEN parameter.
PHYSICALPAGES is an AUTOGEN parameter.
205 – PIOPAGES
PIOPAGES specifies the size of the process I/O segment, which
holds data structures and buffer pool space for RMS to use
when it handles I/O that involves process-permanent files. Once
PIOPAGES is reset in SYSGEN, any new process receives the changed
value.
Beginning with OpenVMS Version 7.2, the default value has been
raised to 575. The setting has been raised to accommodate the
increased demands for process-permanent memory that result from
changes made to RMS file-naming parsing in Version 7.2.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
PIOPAGES is an AUTOGEN and DYNAMIC parameter.
206 – PIXSCAN
PIXSCAN specifies the number of process index slots scanned each
second for computable or computable-outswapped processes. These
processes receive an automatic priority boost for 1 quantum,
unless the priority of the currently executing process is greater
than 15. The priority boost is done to avoid potential deadlocks
on the system.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
PIXSCAN is an AUTOGEN and DYNAMIC parameter.
207 – POOLCHECK
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
POOLCHECK is used to investigate frequent and inexplicable
failures in a system. When POOLCHECK is enabled, pool-checking
routines execute whenever pool is deallocated or allocated.
Two loadable forms of SYSTEM_PRIMITIVES.EXE are available at
boot time. The default image, which contains no pool-checking
code and no statistics maintenance, is loaded when POOLCHECK
is set to zero. When POOLCHECK is set to a nonzero value, the
monitoring version of SYSTEM_PRIMITIVES.EXE, which contains both
pool-checking code and statistics maintenance, is loaded.
Setting the SYSTEM_CHECK parameter to 1 has the effect of setting
POOLCHECK to %X616400FF. For further information about pool
checking, see the OpenVMS VAX Device Support Manual, (which is
archived).
POOLCHECK is a DYNAMIC parameter. However, for a change in its
value to have any effect, POOLCHECK must be non-0 at boot time
(to load the monitoring version of SYSTEM_PRIMITIVES.EXE).
208 – POOLPAGING
POOLPAGING enables (1) paging of pageable dynamic pool.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
209 – POWEROFF
POWEROFF enables or disables software requests to the console
firmware to remove power from the system. This parameter should
normally be turned ON (1) to allow software to make power-off
requests. However, POWEROFF can be set to OFF (0) to disable
software power-off requests.
If firmware or hardware support for the power-off request is not
implemented, the shut-down procedure will leave the system halted
but fully powered.
POWEROFF is a DYNAMIC parameter.
210 – PQL_DASTLM
PQL_DASTLM sets the default limit on the number of pending ASTs
for a process created by the Create Process ($CREPRC) system
service or the DCL command RUN (Process).
PQL_DASTLM has the DYNAMIC and GEN attributes.
211 – PQL_DBIOLM
PQL_DBIOLM sets the default buffered I/O count limit for the
number of outstanding buffered I/O operations permitted to a
process created by the Create Process ($CREPRC) system service or
the DCL command RUN (Process).
PQL_DBIOLM has the DYNAMIC and GEN attributes.
212 – PQL_DBYTLM
PQL_DBYTLM sets the default buffered I/O byte count limit for the
amount of buffered space available to a process created by the
Create Process ($CREPRC) system service or the DCL command RUN
(Process).
PQL_DBYTLM has the DYNAMIC and GEN attributes.
213 – PQL_DCPULM
PQL_DCPULM sets the default CPU time limit for a process created
by the Create Process ($CREPRC) system service or the DCL command
RUN (Process). PQL_DCPULM specifies the time limit in increments
of 10 milliseconds.
The default value of 0 imposes no limit on CPU time usage and is
typically the correct value for this parameter.
PQL_DCPULM has the DYNAMIC and GEN attributes.
214 – PQL_DDIOLM
PQL_DDIOLM sets the default direct I/O limit for a process
created by the Create Process ($CREPRC) system service or the
DCL command RUN (Process).
PQL_DDIOLM has the DYNAMIC and GEN attributes.
215 – PQL_DENQLM
PQL_DENQLM sets the default enqueue limit for a process created
by the Create Process ($CREPRC) system service or the DCL command
RUN (Process).
PQL_DENQLM has the DYNAMIC and GEN attributes.
216 – PQL_DFILLM
PQL_DFILLM sets the default open file limit for a process created
by the Create Process ($CREPRC) system service or the DCL command
RUN (Process).
PQL_DFILLM has the DYNAMIC and GEN attributes.
217 – PQL_DJTQUOTA
PQL_DJTQUOTA sets the default job table byte count quota for a
process created by the Create Process ($CREPRC) system service or
the DCL command RUN (Process). PQL_DJTQUOTA specifies the number
of bytes of paged pool allocated to the job table. The default
value is usually adequate, unless a large number of job logical
names or temporary mailboxes are used.
PQL_DJTQUOTA is a DYNAMIC parameter.
218 – PQL_DPGFLQUOTA
PQL_DPGFLQUOTA sets the default page file quota for a process
created by the Create Process ($CREPRC) system service or the DCL
command RUN (Process). VSI recommends that this parameter not be
smaller than the PQL_DWSEXTENT parameter.
PQL_DPGFLQUOTA has the DYNAMIC and GEN attributes. On VAX
systems, PQL_DPGFLQUOTA is also an AUTOGEN parameter.
219 – PQL_DPRCLM
PQL_DPRCLM sets the default subprocess limit for a process
created by the Create Process ($CREPRC) system service or the
DCL command RUN (Process).
PQL_DPRCLM has the DYNAMIC and GEN attributes.
220 – PQL_DTQELM
PQL_DTQELM sets the default number of timer queue entries for a
process created by the Create Process ($CREPRC) system service or
the DCL command RUN (Process).
PQL_DTQELM has the DYNAMIC and GEN attributes.
221 – PQL_DWSDEFAULT
PQL_DWSDEFAULT sets the default working set size for a process
created by the Create Process ($CREPRC) system service or the DCL
command RUN (Process).
PQL_DWSDEFAULT has the AUTOGEN and GEN attributes.
222 – PQL_DWSEXTENT
PQL_DWSEXTENT sets the default working set extent for a process
created by the Create Process ($CREPRC) system service or the DCL
command RUN (Process).
PQL_DWSEXTENT has the AUTOGEN, DYNAMIC, and GEN attributes.
223 – PQL_DWSQUOTA
PQL_DWSQUOTA sets the default working set quota for a process
created by the Create Process ($CREPRC) system service or the DCL
command RUN (Process).
PQL_DWSQUOTA has the AUTOGEN, DYNAMIC, and GEN attributes.
224 – PQL_MASTLM
PQL_MASTLM sets a minimum limit on the number of pending ASTs for
a process created by the Create Process ($CREPRC) system service
or the DCL command RUN (Process).
PQL_MASTLM has the DYNAMIC and GEN attributes.
225 – PQL_MBIOLM
PQL_MBIOLM sets the minimum buffered I/O limit for a process
created by the Create Process ($CREPRC) system service or the DCL
command RUN (Process).
PQL_MBIOLM has the DYNAMIC and GEN attributes.
226 – PQL_MBYTLM
PQL_MBYTLM sets the minimum buffered I/O byte limit for a process
created by the Create Process ($CREPRC) system service or the DCL
command RUN (Process).
PQL_MBYTLM has the DYNAMIC and GEN attributes.
227 – PQL_MCPULM
PQL_MCPULM sets the minimum CPU time limit in increments of
10 milliseconds for a process created by the Create Process
($CREPRC) system service or the DCL command RUN (Process).
PQL_MCPULM has the DYNAMIC and GEN attributes.
228 – PQL_MDIOLM
PQL_MDIOLM sets the minimum direct I/O limit for a process
created by the Create Process ($CREPRC) system service or the
DCL command RUN (Process).
PQL_MDIOLM has the DYNAMIC and GEN attributes.
229 – PQL_MENQLM
PQL_MENQLM sets the minimum limit on the number of locks that can
be queued at one time by a process created by the Create Process
($CREPRC) system service or the DCL command RUN (Process).
PQL_MENQLM has the DYNAMIC and GEN attributes.
230 – PQL_MFILLM
PQL_MFILLM sets the minimum open file limit for a process created
by the Create Process ($CREPRC) system service or the DCL command
RUN (Process).
PQL_MFILLM has the DYNAMIC and GEN attributes.
231 – PQL_MJTQUOTA
PQL_MJTQUOTA sets the minimum job table byte count quota for a
process created by the Create Process ($CREPRC) system service or
the DCL command RUN (Process).
PQL_MJTQUOTA is a DYNAMIC parameter.
232 – PQL_MPGFLQUOTA
On VAX systems, PQL_MPGFLQUOTA sets the minimum page file quota
for a process created by the Create Process ($CREPRC) system
service or the DCL command RUN (Process). VSI recommends that this
parameter be no smaller than PQL_MWSEXTENT.
On Alpha and Integrity servers, PQL_MPGFLQUOTA sets the minimum
pagelet file quota for a process created by the Create Process
($CREPRC) system service or the DCL command RUN (Process).
PQL_MPQFLQUOTA has the DYNAMIC and GEN attributes. On VAX
systems, PQL_MPQFLQUOTA is also an AUTOGEN parameter.
233 – PQL_MPRCLM
PQL_MPRCLM sets the minimum subprocess limit for a process
created by the Create Process ($CREPRC) system service or the
DCL command RUN (Process).
PQL_MPRCLM has the DYNAMIC and GEN attributes.
234 – PQL_MTQELM
PQL_MTQELM sets the minimum number of timer queue entries for a
process created by the Create Process ($CREPRC) system service or
the DCL command RUN (Process).
PQL_MTQELM has the DYNAMIC and GEN attributes.
235 – PQL_MWSDEFAULT
PQL_MWSDEFAULT sets the minimum default working set size for a
process created by the Create Process ($CREPRC) system service or
the DCL command RUN (Process).
This value overrides a smaller quantity that is set for a user in
AUTHORIZE.
PQL_MWSDEFAULT has the AUTOGEN and GEN attributes.
236 – PQL_MWSEXTENT
PQL_MWSEXTENT sets the minimum working set extent for a process
created by the Create Process ($CREPRC) system service or the DCL
command RUN (Process).
This value overrides a smaller quantity set for a user in
AUTHORIZE.
PQL_MWSEXTENT has the AUTOGEN, DYNAMIC, and GEN attributes.
237 – PQL_MWSQUOTA
PQL_MWSQUOTA sets the minimum working set quota for a process
created by the Create Process ($CREPRC) system service or the DCL
command RUN (Process).
This value overrides a smaller quantity set for a user in
AUTHORIZE.
PQL_MWSQUOTA has the AUTOGEN, DYNAMIC, and GEN attributes.
238 – PRCPOLINTERVAL
PRCPOLINTERVAL specifies, in seconds, the polling interval used
to look for Systems Communications Services (SCS) applications,
such as the connection manager and mass storage control protocol
disks, on other nodes. All discovered nodes are polled during
each interval.
This parameter trades polling overhead against quick recognition
of new systems or servers as they appear.
PRCPOLINTERVAL is a DYNAMIC parameter. On Alpha and Integrity
servers, PRCPOLINTERVAL is also an AUTOGEN parameter.
239 – PRIORITY_OFFSET
PRIORITY_OFFSET specifies the difference in priority required
by the scheduler for one process to preempt the current process.
A value of 2, for example, means that if the current process
is executing at priority 1, a computable process at priority 2
or 3 is not allowed to preempt the current process. However, a
priority 4 or higher process can preempt the current process.
This mechanism affects only normal priority (0-15) processes. The
default value is 0.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
240 – PROCSECTCNT
PROCSECTCNT sets the number of section descriptors that a process
can contain. Each section descriptor increases the fixed portion
of the process header by 32 bytes.
Set a value greater than the maximum number of image sections
in any section to be run, as indicated by the linkage memory
allocation map for the image.
PROCSECTCNT has the AUTOGEN and GEN attributes.
241 – PU_OPTIONS
PU_OPTIONS is reserved for VSI use only.
242 – QDSKINTERVAL
QDSKINTERVAL establishes, in seconds, the disk quorum polling
interval. The default value is 3.
243 – QDSKVOTES
QDSKVOTES specifies the number of votes contributed by a quorum
disk in a cluster.
244 – QUANTUM
QUANTUM defines the following:
o Processor time: maximum amount of processor time a process
can receive before control passes to another process of equal
priority that is ready to compute
o Balance set residency: minimum amount of service a compute-
state process must receive before being swapped out to
secondary storage
QUANTUM has the DYNAMIC and MAJOR attributes. On Alpha and
Integrity servers, QUANTUM also has the AUTOGEN attribute.
245 – RAD_SUPPORT
RAD_SUPPORT enables RAD-aware code to be executed
on systems that support Resource Affinity Domains (RADs);
for example, AlphaServer GS160 systems and Integrity
cell-based servers or BL8x0c i2 servers. A RAD is a set of
hardware components (CPUs and memory) with common access
characteristics.
Bits are defined in the RAD_SUPPORT parameter as follows:
RAD_SUPPORT (default is 207 for Alpha and 10944667
for Integrity servers)
___________________________________________________
3 2 2 2 2 1 1
1 8 7 4 3 6 5 8 7 0
+-----+-----+-----------+-----------+-----------+
|00|00| skip|ss|gg|ww|pp|00|00|00|00|0p|df|cr|ae|
+-----+-----+-----------+-----------+-----------+
Bit 0 (e): Enable - Enables RAD support
Bit 1 (a): Affinity - Enables Soft RAD Affinity (SRA) scheduling
Also enables the interpretation of the skip
bits, 24-27.
Bit 2 (r): Replicate - Enables system-space code replication
Bit 3 (c): Copy - Enables copy on soft fault
Bit 4 (f): Fault - Enables special page fault allocation
Also enables the interpretation of the
allocation bits, 16-23.
Bit 5 (d): Debug - Reserved to VSI
Bit 6 (p): Pool - Enables per-RAD non-paged pool
Bits 7-15: - Reserved to VSI
Bits 16-23: - If bit 4 is set, bits 16-23 are interpreted
as follows:
Bits 16,17 (pp): Process = Pagefault on process (non global)
pages
Bits 18,19 (ww): Swapper = Swapper's allocation of pages for
processes
Bits 20,21 (gg): Global = Pagefault on global pages
Bits 22,23 (ss): System = Pagefault on system space pages
Encodings for pp, ww, gg, ss:
Current (0) - allocate PFNs from the current CPU's RAD
Random (1) - allocate PFNs using the "random" algorithm
Base (2) - allocate PFNs from the operating system's "base"
RAD
Home (3) - allocate PFNs from the current process's home RAD
If bits 16-23 are 0, the defaults for pp, ww, gg, ss are interpreted
as follows:
Process = home RAD
Swapper = current RAD (also sets home RAD for process)
Global = random RAD
System = base RAD
Bits 24-27: - If bit 1 is set, bits 24-27 are interpreted
as a skip count value (power of 2). Example: If
bits 24-27 contain a 3, the skip count is 8.
If bits 24-27 contain a 5, the skip count is 32.
If bits 24-27 are 0, the default of 16 is used
as the skip count.
Bits 28-31: - Reserved to VSI
For more information about using OpenVMS RAD features, see the
OpenVMS Alpha Galaxy and Partitioning Guide or VSI OpenVMS
Version 8.4 New Features and Documentation Overview.
RAD_SUPPORT has the GEN attribute.
REALTIME_SPTS has the DYNAMIC, GEN, and MAJOR attributes.
246 – RECNXINTERVAL
RECNXINTERVAL establishes the polling interval, in seconds,
during which to attempt reconnection to a remote system.
RECNXINTERVAL is a DYNAMIC parameter. On Alpha and Integrity
servers, RECNXINTERVAL is also an AUTOGEN parameter.
247 – RESALLOC
RESALLOC controls whether resource allocation checking is
performed. The default value of 0 disables resource allocation
checking.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
248 – RESHASHTBL
RESHASHTBL defines the number of entries in the lock management
resource name hash table. Each entry requires 4 bytes. A typical
tuning goal is to have the RESHASHTBL parameter about four times
larger than the total number of resources in use on the system.
Managers of systems with memory constraints or systems that are
not critically dependent on locking speed could set the table to
a smaller size.
RESHASHTBL has the AUTOGEN, FEEDBACK, and MAJOR attributes.
249 – RJOBLIM
RJOBLIM defines the maximum number of remote terminals allowed in
the system at any one time.
RJOBLIM is a DYNAMIC parameter.
250 – RMS_CONPOLICY
RMS_CONPOLICY specifies the policy to be used for dealing with
high-contention write-shared files. This dynamic parameter can
be used to ensure fairness between lock conversions and new lock
requests.
Possible values are the following:
Value Explanation
NEVER (Default) Never use the higher overhead option
to improve fairness for any write-shared files
accessed on the system; minimal overhead.
SOMETIMES Use this option for fairer bucket access (but
higher overhead) to any write-shared files with
global buffers enabled that are accessed on the
system.
ALWAYS Use this option for fairer bucket access (but
higher overhead) to all write-shared files
accessed on the system.
You can set this system parameter with the DCL command SET RMS_
DEFAULT/SYSTEM/CONTENTION_POLICY=value and display the parameter
with the DCL command SHOW RMS_DEFAULT.
RMS_CONPOLICY is a DYNAMIC parameter.
251 – RMSD*
RMSD1, RMSD2, RMSD3, RMSD4, RMSD5, RMSD6, and RMSD7 are special
parameters reserved for VSI use.
RMSD* parameters are DYNAMIC.
252 – RMS_DFLRL
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
RMS_DFLRL is a DYNAMIC parameter.
253 – RMS_DFMBC
RMS_DFMBC specifies a default multiblock count only for record
I/O operations, where count is the number of blocks to be
allocated for each I/O buffer.
You can set this system parameter with the DCL command SET RMS_
DEFAULT/SYSTEM and display the parameter with the SHOW RMS_
DEFAULT command.
RMS_DFMBC is an AUTOGEN and DYNAMIC parameter.
254 – RMS_DFMBFIDX
RMS_DFMBFIDX establishes the default RMS multibuffer count for
indexed sequential disk operations. This value defines the number
of I/O buffers that RMS allocates for each indexed file. For
sequential access, a larger number that allows some of the index
buckets to remain in memory can improve performance.
You can set this system parameter with the DCL command
SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_
DEFAULT.
RMS_DFMBFIDX is an AUTOGEN and DYNAMIC parameter.
255 – RMS_DFMBFREL
RMS_DFMBFREL establishes the default RMS multibuffer count for
relative disk operations. This value defines the number of I/O
buffers that RMS allocates for each relative file.
You can set this system parameter with the DCL command
SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_
DEFAULT.
RMS_DFMBFREL is an AUTOGEN and DYNAMIC parameter.
256 – RMS_DFMBFSDK
RMS_DFMBFSDK establishes the default RMS multibuffer count for
sequential disk operations. This value defines the number of I/O
buffers that RMS allocates for sequential disk files.
The default value is usually adequate. However, if read-ahead
or write-behind operations are used, a larger number improves
performance.
You can set this system parameter with the DCL command
SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_
DEFAULT.
RMS_DFMBFSDK is an AUTOGEN and DYNAMIC parameter.
257 – RMS_DFMBFSMT
RMS_DFMBFSMT establishes the default RMS multibuffer count for
magnetic tape operations. This value defines the number of I/O
buffers that RMS allocates for magnetic tape files.
You can set this system parameter with the DCL command
SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_
DEFAULT.
RMS_DFMBFSMT is an AUTOGEN and DYNAMIC parameter.
258 – RMS_DFMBFSUR
RMS_DFMBFSUR establishes the default multibuffer count for unit
record devices.
You can set this system parameter with the DCL command
SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_
DEFAULT.
RMS_DFMBFSUR is an AUTOGEN and DYNAMIC parameter.
259 – RMS_DFNBC
RMS_DFNBC specifies a default block count for network access to
remote, sequential, indexed sequential, and relative files.
The network block count value represents the number of blocks
that RMS is prepared to allocate for the I/O buffers used to
transmit and receive data. The buffer size used for remote file
access, however, is the result of a negotiation between RMS and
the remote file access listener (FAL). The buffer size chosen is
the smaller of the two sizes presented.
Thus, RMS_DFNBC places an upper limit on the network buffer size
that is used. It also places an upper limit on the largest record
that can be transferred to or from a remote file. In other words,
the largest record that can be transferred must be less than or
equal to RMS_DFNBC multiplied by 512 bytes.
You can set this system parameter with the DCL command
SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_
DEFAULT.
RMS_DFNBC is an AUTOGEN and DYNAMIC parameter.
260 – RMS_EXTEND_SIZE
RMS_EXTEND_SIZE specifies the number of blocks by which files
are extended as they are written. This number should be chosen to
balance the amount of extra disk space wasted at the ends of each
file against the performance improvement provided by making large
extents infrequently.
When small disk quotas are used, specify a small number such as
the disk cluster size to prevent the user's disk quota from being
consumed. If the value of 0 is used, RMS allocates large extents
and truncates the file back to its actual usage when it closes.
You can set this system parameter with the DCL command
SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_
DEFAULT.
RMS_EXTEND_SIZE is a DYNAMIC parameter.
261 – RMS_FILEPROT
RMS_FILEPROT determines the default file protection for system
processes such as those that create the error log, operator log,
and job controller. It also determines default file protection
for processes created by the job controller (all interactive and
batch processes).
Because a process always inherits its default file protection
from its creator process, RMS_FILEPROT determines default file
protection only for users who do not execute the DCL command SET
PROTECTION/DEFAULT in their login command procedures or during
interactive sessions.
The protection is expressed as a mask. (See the discussion of
the $CRMPSC system service in the VSI OpenVMS System Services
Reference Manual for more information about specifying protection
masks.) By default, the mask is 64000 (decimal) or FA00
(hexadecimal), which represents the following protection:
(S:RWED,O:RWED,G:RE,W:)
262 – RMS_HEURISTIC
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
RMS_HEURISTIC is a DYNAMIC parameter.
263 – RMS_PATH_TMO
The RMS path cache in each process holds entries that translate
DVI+DID+name to new DVI+DID. These are used to greatly speed
up directory path walks. Cache entries representing ordinary
directory lookups are invalidated through the volume directory
sequence number mechanism (UDB$L_DIRSEQ), which is clocked
on every volume dismount and each time a directory is deleted
or renamed. However, there is no convenient mechanism for
invalidating a cache entry that represents a symlink, whose
interpretation is affected by logical names or modification of
the symlink. The only way to eliminate stale cache entries is
with a timeout. This parameter is the system-wide cache timeout.
Special values:
1 = don't keep cache entries
-1 = keep cache entries forever
RMS_PATH_TMO is a DYNAMIC parameter.
264 – RMS_PROLOGUE
RMS_PROLOGUE specifies the default prologue RMS uses to create
indexed files. The default value 0 specifies that RMS should
determine the prologue based on characteristics of the file. A
value of 2 specifies Prologue 2 or Prologue 1, and 3 specifies
Prologue 3. The RMS prologues are described in the OpenVMS Record
Management Services Reference Manual.
RMS_PROLOGUE is a DYNAMIC parameter.
265 – RMS_SEQFILE_WBH
(Alpha and Integrity servers) RMS_SEQFILE_WBH can enable the
RMS writebehind feature as a system default for any unshared
sequential disk file if the file is opened for image I/O with
write access specified. The possible settings are the following:
Setting Description
0 (default) Do not enable writebehind feature. Preserve prior
behavior of using writebehind only if the user
requests it by setting RAB$V_WBH in RAB$L_ROP.
1 Enable writebehind feature as system default,
including the allocation of at least two local
buffers.
RMS_SEQFILE_WBH is a DYNAMIC parameter.
266 – S0_PAGING
S0_PAGING controls paging of system code:
o Setting bit 0 disables paging of all Exec code and data.
o Setting bit 1 disables paging of all RMS code and data.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
267 – S2_SIZE
(Alpha and Integrity servers) S2_SIZE is the number of megabytes
to reserve for S2 space. This value does not include the size
required for extended file cache (XFC).
268 – SAVEDUMP
If the dump file is saved in the page file, SAVEDUMP specifies
whether the page file is saved until the dump file is analyzed.
The default value 0 specifies that the page file should not be
retained. A value of 1 specifies that the dump written to the
page file should be retained until either copied or released
using the SDA utility.
269 – SCHED_FLAGS
Special DYNAMIC parameter reserved for VSI use.
270 – SCH_HARD_OFFLD
The scheduler hard off-load parameter is a CPU bitmask parameter.
The bits correspond to CPU IDs. For any bit set, the OpenVMS
scheduler does not schedule processes on this CPU unless the
process has hard affinity set for the CPU. In addition, a process
with the PRIMARY capability requirement will ignore the bit
corresponding to the primary CPU.
SCH_HARD_OFFLD is a DYNAMIC parameter.
271 – SCH_SOFT_OFFLD
The scheduler soft off-load parameter is a CPU bitmask parameter.
The bits correspond to CPU IDs. For any bit set, the OpenVMS
scheduler tries to avoid scheduling processes on this CPU.
However, if no other idle CPUs exist, processes are still
scheduled on this CPU.
SCH_SOFT_OFFLD is a DYNAMIC parameter.
272 – SCSBUFFCNT
On VAX systems, SCSBUFFCNT is the number of buffer descriptors
configured for all systems communication architecture (SCA). If
an SCA device is not configured on your system, this parameter is
ignored. Generally speaking, each data transfer needs a buffer
descriptor and thus the number of buffer descriptors can be
a limit on the number of possible simultaneous I/Os. Various
performance monitors report when a system is out of buffer
descriptors for a given workload which is an indication that
a larger value for SCSBUFFCNT is worth considering. Note that
AUTOGEN provides feedback for this parameter on VAX systems only.
On Alpha and Integrity servers, the system communication services
(SCS) buffers are allocated as needed, and SCSBUFFCNT is reserved
for VSI use only.
SCSBUFFCNT has the AUTOGEN, FEEDBACK, and GEN attributes.
273 – SCSFLOWCUSH
Specifies the lower limit for receive buffers at which point
system communication services (SCS) starts to notify the remote
SCS of new receive buffers. For each connection, SCS tracks the
number of receive buffers available. SCS communicates this number
to the SCS at the remote end of the connection. However, SCS does
not need to do this for each new receive buffer added. Instead,
SCS notifies the remote SCS of new receive buffers if the number
of receive buffers falls as low as the SCSFLOWCUSH value.
The default value is adequate on most systems. If a systems
communication architecture (SCA) port is not configured on your
system, this parameter is ignored.
SCSFLOWCUSH is a DYNAMIC parameter.
274 – SCSI_ERROR_POLL
If an error occurs while a particular initiator is accessing
a SCSI device, that error is latched for all other initiators
and is not unlatched and reported to the other initiators until
the next time they access the device. Therefore, if the other
initiators do not access the device in a timely manner, the
reporting of the error can be greatly delayed, which can cause
confusion.
The purpose of SCSI_ERROR_POLL is to cause OpenVMS to send a
SCSI Test Unit Ready command every hour to each SCSI disk, in
an attempt to force latched errors to become unlatched and to
be reported immediately. SCSI_ERROR_POLL has a default value of
1. It can, however, be set to 0 by the user in order to stop the
error polling activity.
The parameter affects SCSI disks connected by Fibre Channel as
well as parallel SCSI. If the disk has multiple paths, then the
error polling is performed on all non-served paths to the disk.
Tapes and other non-disk devices are not subject to this error
polling, regardless of the parameter setting.
SCSI_ERROR_POLL is a DYNAMIC parameter.
SCSI_NOAUTO is a DYNAMIC parameter.
275 – SCSICLUSTER_P[1-4]
(Alpha only) SCSICLUSTER_P[1-4] parameters allow non-HP
peripherals (CPU-lookalikes) in SCSI clusters.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
276 – SCSMAXDG
This parameter is reserved for VSI use only.
SCSMAXDG has the GEN attribute.
277 – SCSMAXMSG
This parameter is reserved for VSI use only.
SCSMAXMSG has the GEN attribute.
278 – SCSNODE
SCSNODE specifies the name of the computer. This parameter is not
dynamic.
Specify SCSNODE as a string of up to six characters. Enclose the
string in quotation marks.
NOTE
The maximum size of six characters is strictly enforced.
SYSBOOT truncates the value of SCSNODE if the size of the
system parameter is set to more than six characters.
If the computer is in an OpenVMS Cluster, specify a value that is
unique within the cluster. Do not specify the null string.
If the computer is running DECnet for OpenVMS, the value must be
the same as the DECnet node name.
SCSNODE has the AUTOGEN and GEN attributes.
279 – SCSRESPCNT
SCSRESPCNT is the total number of response descriptor table
entries (RDTEs) configured for use by all system applications.
If SCA or DSA ports are not configured on your system, the system
ignores SCSRESPCNT.
SCSRESPCNT has the AUTOGEN, FEEDBACK, and GEN attributes.
280 – SCSSYSTEMID
Specifies a number that identifies the computer. This parameter
is not dynamic. SCSSYSTEMID is the low-order 32 bits of the 48-
bit system identification number.
If the computer is in an OpenVMS Cluster, specify a value that is
unique within the cluster. Do not use zero as the value.
If the computer is running DECnet for OpenVMS, calculate the
value from the DECnet address using the following formula:
SCSSYSTEMID = ((DECnet area number) * 1024) + (DECnet node number)
Example: If the DECnet address is 2.211, calculate the value as
follows:
SCSSYSTEMID = (2 * 1024) + 211 = 2259
SCSSYSTEMID has the GEN attribute.
281 – SCSSYSTEMIDH
Specifies the high-order 16 bits of the 48-bit system
identification number. This parameter must be set to 0. It is
reserved by VSI for future use.
SCSSYSTEMIDH has the GEN attribute.
282 – SECURITY_POLICY
SECURITY_POLICY allows a system to run in a C2 or B1
configuration and to subset out particular pieces of
functionality-to exclude functionality that is outside the
evaluated configuration or to preserve compatibility with
previous versions of the operating system. See the VSI OpenVMS
Guide to System Security for further information about the C2 and
B1 evaluated configurations.
The following bits are defined:
Bit Description
0 Obsolete.
1 Allows multiple user names to connect to DECW$SERVER.
2 Allows unevaluated DECwindows transports (such as TCP/IP).
3 Allows $SIGPRC and $PRCTERM to span job trees.
4 Allows security profile changes to protected objects on
a local node when the object server is absent and cannot
update the cluster database VMS$OBJECTS.DAT.
5 Allows creation of protected objects on a local node when
the object server is absent and cannot update the cluster
database VMS$OBJECTS.DAT.
6 Allows SPAWN or LIB$SPAWN commands in CAPTIVE accounts.
7 Reserved to VSI.
8 Reserved to VSI.
9 Disables password synchronizations among ACME agents on
a systemwide pasis. This is functionally equivalent to
the SYS$SINGLE_SIGNON logical name bit mask value 4 for
LOGINOUT.
10 Allows privileged applications to successfully authenticate
a user whose principal name maps to a SYSUAF record that is
either expired or whose modal restrictions would otherwise
prevent the account from being used.
A SYSUAF record that is disabled or password-expired (in
the case of traditional OpenVMS authentication) cannot be
bypassed in this manner.
An application with SECURITY privilege specifies the
SYS$ACM ACME$M_NOAUTHORIZE function modifier to override
authorization checks.
11 Allows any record in the SYSUAF file to be mapped using
external authentication.
12 Allows intrusions on a clusterwide or local basis. (If the
bit is cleared, intrusions are clusterwide.)
13 Reserved to VSI.
14 Allows the internal name and backlink of files and
directories to be read if the user has either execute or
read access to the file or directory. If this bit is clear,
read access is required.
Setting this bit allows the full POSIX pathname of a file
or directory to be displayed when some of the directories
in the path are execute-only to the user. This feature is
required in the following environments:
o POSIX pathnames are in use.
o The BASH shell or other GNV components are in use.
o Applications are using the realpath(), getcwd(),
getpwnam(), and related C runtime library functions.
The default value of 7 preserves compatibility with existing
DECwindows Motif behavior. A value of 0 disables all unevaluated
configurations.
283 – SETTIME
SETTIME enables (1) or disables (0) solicitation of the time of
day each time the system is booted. This parameter should usually
be off (0), so that the system sets the time of day at boot time
to the value of the processor time-of-day register. You can reset
the time after the system is up with the DCL command SET TIME
(see the VSI OpenVMS DCL Dictionary).
284 – SHADOW_D1-D5
Special DYNAMIC parameters reserved for VSI use.
285 – SHADOW_ENABLE
Special parameter reserved for VSI use.
286 – SHADOWING
SHADOWING loads the host-based volume shadowing driver. See VSI
Volume Shadowing for OpenVMS for more information about setting
system parameters for volume shadowing.
Specify one of the following values:
Value Description
0 No shadowing is enabled; SHDRIVER is not loaded. This is
the default value.
2 Host-based volume shadowing enabled; SHDRIVER is loaded.
Host-based volume shadowing provides shadowing of all
disks located on a standalone system or an OpenVMS Cluster
system.
287 – SHADOW_HBMM_RTC
(Alpha and Integrity servers) SHADOW_HBMM_RTC specifies, in
seconds, how frequently each shadow set on this system has its
modified block count compared with the reset threshold. If the
modified block count exceeds the reset threshold, the bitmap for
that shadow set is zeroed. This comparison is performed for all
shadow sets mounted on the system that have HBMM bitmaps.
The reset threshold is specified by the RESET_THRESHOLD keyword
in the /POLICY qualifier of the SET SHADOW command.
When the comparison is made, the modified block count might
exceed the reset threshold by a small increment or by a much
larger amount. The difference depends on the write activity to
the volume and on the setting of this parameter.
SHADOW_HBMM_RTC is a DYNAMIC parameter.
288 – SHADOW_MAX_COPY
The value of SHADOW_MAX_COPY controls how many parallel copy
threads are allowed on a given node.
Carefully consider the needs of each shadowed node when you
set this parameter. Too high a value for SHADOW_MAX_COPY can
affect performance by allowing too many copy threads to operate
in parallel. Too low a value unnecessarily restricts the number
of threads your system can effectively handle.
See VSI Volume Shadowing for OpenVMS for more information about
setting system parameters for volume shadowing.
SHADOW_MAX_COPY has the AUTOGEN and DYNAMIC attributes.
289 – SHADOW_MAX_UNIT
SHADOW_MAX_UNIT specifies the maximum number of shadow sets that
can exist on a system. The setting must be equal to or greater
than the number of shadow sets you plan to have on a system.
Dismounted shadow sets, unused shadow sets, and shadow sets with
no write bitmaps allocated to them are included in the total.
NOTE
Review this default carefully. The setting must be equal to
or greater than the number of shadow sets you plan to have
on a system. If you attempt to mount more shadow sets than
the number specified by SHADOW_MAX_UNIT, the MOUNT command
will fail. Dismounted shadow sets, unused shadow sets, and
shadow sets with no write bitmaps allocated to them are
included in the count for SHADOW_MAX_UNIT.
On Alpha and Integrity servers, the default value for this system
parameter is 500, which consumes 24 KB of main memory.
If you do not plan to use Volume Shadowing for OpenVMS, you can
change the setting to its minimum of 10 (which consumes 480 bytes
of main memory). Setting the default to its minimum frees up 23.5
KB of main memory on an OpenVMS Alpha or Integrity servers and
4.5 KB of main memory on a VAX system. (The maximum value of this
parameter is 10,000.)
This system parameter is not dynamic; that is, a reboot is
required when you change the setting.
290 – SHADOW_MBR_TMO
SHADOW_MBR_TMO controls the amount of time the system tries to
fail over physical members of a shadow set before removing them
from the set. The SHADOW_MBR_TMO parameter replaces the temporary
VMSD3 parameter used in prior releases.
The SHADOW_MBR_TMO parameter is valid for use only with Phase II
of Volume Shadowing for OpenVMS. You cannot set this parameter
for use with Phase I, which is obsolete.
Use the SHADOW_MBR_TMO parameter (a word) to specify the number
of seconds, in decimal from 1 to 65,535, during which recovery
of a repairable shadow set is attempted. If you do not specify
a value or if you specify 0, the default delay of 120 seconds is
used.
Because SHADOW_MBR_TMO is a dynamic parameter, you should use the
SYSGEN command WRITE CURRENT to permanently change its value.
SHADOW_MBR_TMO is a DYNAMIC parameter.
291 – SHADOW_PSM_RDLY
When a copy or merge operation is needed on a shadow set that is
mounted on more than one system, the shadowing driver attempts
to perform the operation on a system that has a local connection
to all the shadow set members. Shadowing implements the copy or
merge operation by adding a time delay based on the number of
shadow set members that are MSCP-served to the system. No delay
is added for local members; a system with all locally accessible
shadow set members usually performs the copy or merge before a
system on which one or more members is served (and therefore is
delayed) does.
SHADOW_PSM_RDLY allows the system manager to adjust the delay
that shadowing adds. By default, the delay is 30 seconds for each
MSCP-served shadow set member. The valid range for the specified
delay is 0 through 65,535 seconds.
When a shadow set is mounted on a system, the value of SHADOW_
PSM_RDLY is used as the default shadow set member recovery delay
for that shadow set. To modify SHADOW_PSM_RDLY for an existing
shadow set, see the SET SHADOW/ /RECOVERY_OPTIONS=DELAY_PER_
SERVED_MEMBER=n command in VSI Volume Shadowing for OpenVMS.
292 – SHADOW_REC_DLY
(Alpha and Integrity servers)
The value of the SHADOW_REC_DLY parameter specifies the length
of time a system waits before it attempts to manage recovery
operations on shadow sets that are mounted on the system.
A shadow set is said to need recovery when a merge or copy
operation is required on that shadow set.
SHADOW_REC_DLY can be used to better predict which systems in
an OpenVMS Cluster performs recovery operations. This is done
by setting lower values of SHADOW_REC_DLY on systems that are
preferred to handle recovery operations and higher values of
SHADOW_REC_DLY on systems that are least preferred to handle
recovery operations.
The range of SHADOW_REC_DLY is 20 to 65535 seconds. The default
value is 20 seconds.
For more information about controlling which systems perform the
merge or copy operations, see VSI Volume Shadowing for OpenVMS.
SHADOW_REC_DLY is a DYNAMIC parameter.
293 – SHADOW_SITE_ID
(Alpha and Integrity servers) This parameter allows a system
manager to define a site value, which Volume Shadowing uses to
determine the best device to perform reads, thereby improving
performance.
The system manager can now define the site value to be used
for all shadow sets mounted on a system. This parameter is an
arbitrary numeric value coordinated by the system manager of
disaster tolerant clusters. Reads from devices that have site
values matching the shadow set's site value are preferred over
reads from devices with different site values. For detailed
information, see the description of the $SET DEVICE/SITE in the
VSI OpenVMS DCL Dictionary and VSI Volume Shadowing for OpenVMS.
SHADOW_SITE_ID is a DYNAMIC parameter.
294 – SHADOW_SYS_DISK
A SHADOW_SYS_DISK parameter value of 1 enables shadowing of the
system disk. A value of 0 disables shadowing of the system disk.
The default value is 0.
Also specify a system disk shadow set virtual unit number with
the SHADOW_SYS_UNIT system parameter, unless the desired system
disk unit number is DSA0.
A value of 4096 enables CI-based minimerge. To enable minimerge
on a system disk, however, you must enable DOSD by setting the
DUMPSTYLE parameter to dump off system disk, as described in the
VSI OpenVMS System Manager's Manual. You can then add the value
4096 to your existing SHADOW_SYS_DISK value. For example, if you
have SHADOW_SYS_DISK set to a value of 1, change it to 4097 to
enable minimerge.
295 – SHADOW_SYS_TMO
The SHADOW_SYS_TMO parameter has the following two distinct uses:
o At system boot time, when this is the first node in the
cluster to boot and to create this specific shadow set. If the
proposed shadow set is not currently mounted in the cluster,
use this parameter to extend the time a booting system waits
for all former members of the shadowed system disk to become
available.
o Once the system successfully mounts the virtual unit and
begins normal operations. In this usage, the SHADOW_SYS_
TMO parameter controls the time the operating system waits
for errant members of a system disk. (Use the SHADOW_MBR_TMO
parameter to control the time the operating system waits for
the errant members of an application disk.)
This parameter applies only to members of the system disk shadow
set. All nodes using a particular system disk shadow set should
have their SHADOW_SYS_TMO parameter set to the same value once
normal operations begin.
The default value is 120 seconds. Change this parameter to a
higher value if you want the system to wait more than the 120-
second default for all members to join the shadow set. You can
set the parameter value to 120 through 65,535 seconds.
296 – SHADOW_SYS_UNIT
Use this parameter for Phase II shadowing only. The SHADOW_SYS_
UNIT parameter is an integer value that contains the virtual unit
number of the system disk. The default value is 0. The maximum
value allowed is 9999. This parameter is effective only when the
SHADOW_SYS_DISK parameter has a value of 1. This parameter should
be set to the same value on all nodes booting off a particular
system disk shadow set. See VSI Volume Shadowing for OpenVMS
for more information about setting system parameters for volume
shadowing.
297 – SHADOW_SYS_WAIT
The SHADOW_SYS_WAIT parameter extends the time a booting system
waits for all current members of a mounted shadowed system disk
to become available to this node. The shadow set must already be
mounted by at least one other cluster node for this parameter to
take effect.
The default value is 480 seconds. Change this parameter to a
higher value if you want the system to wait more than the 480-
second default for all members to join the shadow set. You can
set the parameter value to 1 through 65,535 seconds.
298 – SMCI_FLAGS
(Alpha Galaxy platforms only) The SMCI_FLAGS parameter controls
operational aspects of SYS$PBDRIVER, the Galaxy Shared Memory
Cluster Interconnect (SMCI).
Bits in the bit mask are the following:
Bit Mask Description
0 0 0 = Do not create local communications channels
(SYSGEN default). Local SCS communications are
primarily used in test situations and are not
needed for normal operations. Not creating local
communications saves resources and overhead.
1 = Create local communications channels.
1 2 0 = Load SYS$PBDRIVER if booting into both a Galaxy
and a Cluster (SYSGEN Default).
1 = Load SYS$PBDRIVER if booting into a Galaxy.
2 4 0 = Minimal console output (SYSGEN default).
1 = Full console output; SYS$PBDRIVER displays
console messages when it creates and tears down
communications channels.
SMCI_FLAGS has the DYNAMIC attribute.
299 – SMCI_PORTS
On systems running OpenVMS Galaxy software, the Shared Memory
Cluster Interconnect (SMCI) system parameter SMCI_PORTS controls
initial loading of SYS$PBDRIVER. This parameter is a bit mask;
bits 0 through 25 each represent a controller letter. If bit 0
is set, which is the default setting, PBAx is loaded (where x
represents the Galaxy Partition ID). If bit 1 is set, PBBx is
loaded, and so on up to bit 25, which causes PBZx to be loaded.
For OpenVMS Alpha Version 7.2 and later, VSI recommends leaving
this parameter at the default value of 1.
Loading additional ports allows multiple paths between Galaxy
instances. In the initial release of the Galaxy software, having
multiple communications channels is not an advantage because
SYS$PBDRIVER does not support fast path. A future release
of OpenVMS will provide Fast Path support for SYS$PBDRIVER,
when multiple CPUs improve throughput by providing multiple
communications channels between instances.
300 – SMP_CPU_BITMAP
This parameter indicates that the corresponding CPU is a bitmap
representing up to 1024 CPUs. Each bit set in this bitmap
indicates that the corresponding CPU automatically attempts
to join the active set in an OpenVMS symmetric multiprocessing
environment when the instance is booted. A cleared bit indicates
that the corresponding CPU is ignored only at boot time; if it is
otherwise viable, the CPU can be started at a later time.
SMP_CPU_BITMAP defaults to all bits set. (CPU 0 through CPU 1023
are enabled for multiprocessing.) Note that the primary processor
is always booted regardless of the setting of the corresponding
bit in the CPU bitmap.
To change the value of SMP_CPU_BITMAP in SYSBOOT or SYSGEN,
specify a list of individual bits or contiguous groups of bits.
For example:
SYSGEN> SET SMP_CPU_BITMAP 0,5,17-21
The command in this example sets bits 0, 5, 17, 18, 19, 20, and
21 in the bitmap and clears all other bits.
This parameter replaces the SMP_CPUS parameter.
301 – SMP_LNGSPINWAIT
SMP_LNGSPINWAIT establishes, in 10-microsecond intervals, the
amount of time a CPU in an SMP system normally waits for access
to a shared resource. This process is called spinwaiting.
Generally spinlocks at IPL <= 8 have long holding times,
therefore have their timeout intervals set to SMP_LNGSPINWAIT
to prevent SPINWAIT timeouts in cases of nested acquisition.
A timeout causes a CPUSPINWAIT bugcheck.
The default value is 3000000 (30,00, 000 10-microsecond intervals
or 30 second).
302 – SMP_SANITY_CNT
SMP_SANITY_CNT establishes, in 10-millisecond intervals, the
timeout period for each CPU in a symmetric multiprocessing (SMP)
system. Each CPU in an SMP system monitors the sanity timer of
one other CPU in the configuration to detect hardware or software
failures. If allowed to go undetected, these failures could cause
the cluster to hang. A timeout causes a CPUSANITY bugcheck.
The default value is 300 milliseconds (30 10-millisecond
intervals).
303 – SMP_SPINWAIT
SMP_SPINWAIT establishes, in 10-microsecond intervals, the amount
of time a CPU in an SMP system normally waits for access to a
shared resource. This process is called spinwaiting.
A timeout causes a CPUSPINWAIT bugcheck.
The default value is 100000 (100,000 10-microsecond intervals or
1 second).
304 – SMP_TICK_CNT
SMP_TICK_CNT sets the frequency of sanity timer checks by each
CPU in a multiprocessing system.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
305 – SSI_ENABLE
(Integrity servers only) This parameter controls the usage of
system service interception. SSI_ENABLE is turned on by default.
System Service Interception is a mechanism that allows user
specified code to run before, after or instead of the intercepted
system service. This mechanism is available on OpenVMS Alpha
Version 6.1 and later and OpenVMS Integrity servers Version
8.3 and later, but the parameter SSI_ENABLE is relevant only
on Integrity server systems.
306 – SSINHIBIT
SSINHIBIT controls whether system services are inhibited (1)
(on a per-process basis). By default, system services are not
inhibited (0).
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
307 – STARTUP_P1-8
The following table describes possible values of STARTUP_P1
through _P8:
STARTUP
Value Description
STARTUP_P1 Specifies the type of system boot the system-
independent startup procedure is to perform when
STARTUP_P1 has one of the following values:
o " "- A full boot is performed.
o "MIN"- A minimum boot that starts only what is
absolutely necessary for the operating system
to run.
STARTUP_P2 Controls the setting of verification during the
execution of the system-independent startup
procedure, STARTUP.COM, when STARTUP_P2 has one
of the values described in the lists below.
STARTUP_P2 can be one of the values shown in the
following list:
o F[ALSE], N[O], 0, " "-Verification is not
enabled; in other words, NOVERIFY is performed.
o T[RUE], Y[ES], 1-Verification is enabled; in
other words, a SET VERIFY is performed.
Alternatively, STARTUP_P2 can be a string
containing one or more of the letters shown in
the following list:
o C-Display various checkpointing messages during
startup.
o D-Log (or Dump) the output from the startup to
a file called SYS$SPECIFIC:[SYSEXE]STARTUP.LOG.
o P-DCL verification is enabled for each
component file, but not for the startup driver.
If both P and V are used, P is ignored.
o V-Full DCL verification is enabled; same as
TRUE.
For more information about STARTUP_P2, see the
SYSMAN command STARTUP SET OPTIONS.
STARTUP_P3 Beginning in OpenVMS Version 7.2, if STARTUP_P3
is set to AGEN, the system executes AUTOGEN at the
end of the startup sequence.
STARTUP_P4 Reserved for future use.
through
STARTUP_P8
308 – SWP_PRIO
SWP_PRIO sets the priority of I/O transfers initiated by the
swapper.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
309 – SWPFAIL
SWPFAIL sets the number of consecutive swap failures allowed
before the swap schedule algorithm is changed to ignore the swap
quantum protection.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
310 – SWPOUTPGCNT
This parameter allows the swapper an alternative mechanism before
actually performing swaps.
On Alpha and Integrity servers, SWPOUTPGCNT defines the minimum
number of pagelets to which the swapper should attempt to reduce
a process before swapping it out. The pagelets taken from the
process are placed into the free-page list.
SWPOUTPGCNT has the DYNAMIC attribute. On VAX systems,
SWPOUTPGCNT also has the AUTOGEN attribute.
311 – SWPRATE
SWPRATE sets the swapping rate (in 10-millisecond units).
This parameter limits the amount of disk bandwidth consumed by
swapping.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
312 – SYSMWCNT
SYSMWCNT sets the quota for the size of the system working set,
which contains the pageable portions of the system, the paged
dynamic pool, RMS, and the resident portion of the system message
file.
While a high value takes space away from user working sets, a low
value can seriously impair system performance. Appropriate values
vary, depending on the level of system use. When the system is
running at full load, check the rate of system faults with the
MONITOR PAGE command of the Monitor utility. An average system
page fault rate of between 0 and 3 page faults per second is
desirable. If the system page fault rate is high, and especially
if the system seems to be slow, you should increase the value of
SYSMWCNT. However, do not set this parameter so high that system
page faulting never occurs.
SYSMWCNT has the AUTOGEN, GEN, and MAJOR attributes.
313 – SYSPFC
SYSPFC sets the number of pages to be read from disk on each
system paging operation.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
314 – SYSSER_LOGGING
(Alpha and Integrity servers) A value of 1 for SYSSER_LOGGING
enables logging of system service requests for a process. The
default is 1.
SYSSER_LOGGING is a DYNAMIC system parameter.
315 – SYSTEM_CHECK
SYSTEM_CHECK investigates intermittent system failures by
enabling a number of run-time consistency checks on system
operation and recording some trace information.
Enabling SYSTEM_CHECK causes the system to behave as if the
following system parameter values are set (although the values
of the following parameters are not actually changed):
Parameter Value Description
BUGCHECKFATAL 1 Crash the system on nonfatal
bugchecks.
POOLCHECK %X616400FF Enable all poolchecking, with
an allocated pool pattern
of %x61616161 ('aaaa') and
deallocated pool pattern of
x64646464 ('dddd').
MULTIPROCESSING 2 Enable full synchronization
checking.
While SYSTEM_CHECK is enabled, the previous settings of the
BUGCHECKFATAL and MULTIPROCESSING parameters are ignored.
However, setting the parameter POOLCHECK to a nonzero value
overrides the setting imposed by SYSTEM_CHECK.
Setting SYSTEM_CHECK creates certain image files that are capable
of the additional system monitoring. These image files are
located in SYS$LOADABLE_IMAGES and can be identified by the
suffix _MON. For information about the type of data checking
performed by SYSTEM_CHECK, see the description of the ACP_
DATACHECK parameter. For information about the performance
implications of enabling SYSTEM_CHECK, see OpenVMS Performance
Management.
316 – TAPE_ALLOCLASS
TAPE_ALLOCLASS determines the tape allocation class for the
system. The tape allocation class creates a unique clusterwide
device name for multiple access paths to the same tape.
The TAPE_ALLOCLASS parameter can also be used to generate a
unique clusterwide name for tape devices with identical unit
numbers.
317 – TAPE_MVTIMEOUT
TAPE_MVTIMEOUT is the time in seconds that a mount verification
attempt continues on a given magnetic tape volume. If the mount
verification does not recover the volume within that time, the
I/O operations outstanding to the volume terminate abnormally.
TAPE_MVTIMEOUT is a DYNAMIC parameter.
318 – TBSKIPWSL
TBSKIPWSL specifies the maximum number of working set list
entries that may be skipped while scanning for a "good" entry
to discard. Setting this parameter to 0 disables skipping.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
319 – TIME_CONTROL
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
TIME_CONTROL is an SMP bit mask parameter that controls debugging
functions. The following bits are defined:
Bit Description
0 Obsolete.
1 (EXE$V_SANITY) Disables the SMP sanity timer support.
2 (EXE$V_NOSPINWAIT) Disables the functional behavior of the
SMP spinwait support.
TIME_CONTROL is a DYNAMIC parameter.
320 – TIMEPROMPTWAIT
TIMEPROMPTWAIT defines the number of seconds that you want a
processor to wait for the time and date to be entered when a
system boot occurs, if the processor's time-of-year clock does
not contain a valid time. (The time unit of micro-fortnights
is approximated as seconds in the implementation.) If the
time specified by TIMEPROMPTWAIT elapses, the system continues
the boot operation, and the date and time are set to the last
recorded time that the system booted.
NOTE
VSI recommends that you set the correct system time before
allowing the system to run, so that all functions using
time-stamping (such as the operator log, the error log,
accounting records, file creation dates, and file expiration
dates) contain correct time values.
Depending on the value specified for the TIMEPROMPTWAIT
parameter, the system acts in one of the following ways:
o If TIMEPROMPTWAIT is 0, no prompt or wait occurs; the system
boots immediately, using the time of the last boot as the
system time.
o If TIMEPROMPTWAIT is a positive number less than 32768, one
prompt is issued and the value dictates how many seconds you
can take to respond with a time. If you do not provide a time
before TIMEPROMPTWAIT elapses, the system boots, using the
time of the last boot as the system time.
o If TIMEPROMPTWAIT is a number in the range of 32768 through
65535, the prompt for the time is issued at intervals starting
with 2 and doubling until 256 seconds is reached. If no
response is received, the prompts restart, with the 2-second
interval. This prompting process repeats indefinitely, until
you specify a time.
321 – TIMVCFAIL
TIMVCFAIL specifies the time required for an adapter or virtual
circuit failure to be detected. VSI recommends that the default
value be used. VSI also recommends that this value be lowered only
in OpenVMS Cluster of three CPUs or less, that the same value
be used on each computer in the cluster, and that dedicated LAN
segments be used for cluster I/O.
TIMVCFAIL is a DYNAMIC parameter.
322 – TMSCP_LOAD
TMSCP_LOAD allows the loading of the tape mass storage control
protocol server software. The TMSCP_LOAD parameter also sets
locally connected tapes served. For information about setting the
TMSCP_LOAD parameter, see VSI OpenVMS Cluster Systems.
Setting TMSCP_LOAD to 0 inhibits the loading of the tape server
and the serving of local tapes. Setting TMSCP to 1 loads the
tape server into memory at the time the system is booted and
makes all directly connected tape drives available clusterwide.
The following table describes the two states of the TMSCP_LOAD
parameter:
State Function
0 Do not load the TMSCP tape server. Do not serve any local
tape devices clusterwide. This is the default value.
1 Load the TMSCP tape server. Serve all local TMSCP tape
devices clusterwide.
TMSCP_LOAD is an AUTOGEN parameter.
323 – TMSCP_SERVE_ALL
TMSCP_SERVE_ALL is a bit mask that controls the serving of tapes.
The settings take effect when the system boots. You cannot change
the settings when the system is running.
Starting with OpenVMS Version 7.2, the serving types are
implemented as a bit mask. To specify the type of serving your
system will perform, locate the type you want in the following
table and specify its value. For some systems, you may want
to specify two serving types, such as serving all tapes except
those whose allocation class does not match. To specify such a
combination, add the values of each type, and specify the sum.
In a mixed-version cluster that includes any systems running
OpenVMS Version 7.1-x or earlier, serving all available tapes
is restricted to serving all tapes except those whose allocation
class does not match the system's allocation class (pre-Version
7.2 meaning). To specify this type of serving, use the value 9,
which sets bit 0 and bit 3. The following table describes the
serving type controlled by each bit and its decimal value:
Value
When
Bit Set Description
Bit 0 1 Serve all available tapes (locally attached and
those connected to HSx and DSSI controllers).
Tapes with allocation classes that differ from the
system's allocation class (set by the ALLOCLASS
parameter) are also served if bit 3 is not set.
Bit 1 2 Serve locally attached (non-HSx and non-DSSI)
tapes.
Bit 2 N/A Reserved.
Bit 3 8 Restrict the serving specified by bit 0. All tapes
except those with allocation classes that differ
from the system's allocation class (set by the
ALLOCLASS parameter) are served.
This is pre-Version 7.2 behavior. If your cluster
includes systems running OpenVMS Version 7.1-x
or earlier, and you want to serve all available
tapes, you must specify 9, the result of setting
this bit and bit 0.
Although the serving types are now implemented as a bit mask, the
values of 0, 1, and 2, specified by bit 0 and bit 1, retain their
original meanings:
o 0 - Do not serve any tapes (the default for earlier versions
of OpenVMS).
o 1 - Serve all available tapes.
o 2 - Serve only locally attached (non-HSx and non-DSSI) tapes.
If the TMSCP_LOAD system parameter is 0, TMSCP_SERVE_ALL is
ignored.
324 – TTY_ALTALARM
TTY_ALTALARM sets the size of the alternate type-ahead buffer
alarm. This value indicates at what point an XOFF should be sent
to terminals that use the alternate type-ahead buffers with the
size specified by the TTY_ALTYPAHD parameter.
325 – TTY_ALTYPAHD
TTY_ALTYPAHD sets the size of the alternate type-ahead buffer.
Use this parameter to allow the block mode terminals and
communications lines to operate more efficiently.
The default value is usually adequate. Do not exceed the maximum
value of 32767 when setting this parameter.
326 – TTY_AUTOCHAR
TTY_AUTOCHAR sets the character the terminal driver echoes when
the job controller has been notified.
TTY_AUTOCHAR is a DYNAMIC parameter.
327 – TTY_BUF
TTY_BUF sets the default line width for terminals.
328 – TTY_CLASSNAME
TTY_CLASSNAME provides the 2-character prefix for the terminal
class driver name that is required when booting. Changing the
prefix can be useful when debugging a new terminal driver.
329 – TTY_DEFCHAR
TTY_DEFCHAR sets the default characteristics for terminals, using
a code derived by summing the following hexadecimal values:
Characteristic Value (Hex) Function
PASSALL 1 Passall.
NOECHO 2 Noecho mode.
NOTYPEAHEAD 4 No type-ahead buffer.
ESCAPE 8 Escape sequence processing.
HOSTSYNC 10 Host can send XON and XOFF.
TTSYNC 20 Terminal can send XON and XOFF.
SCRIPT 40 Internal use only.
LOWER 80 Lowercase.
MECHTAB 100 Mechanical tabs.
WRAP 200 Wraparound at end of line.
CRFILL 400 Perform carriage return fill.
LFFILL 800 Perform line feed fill.
SCOPE 1000 Terminal is a scope.
REMOTE 2000 Internal use only.
EIGHTBIT 8000 Eight-bit terminal.
MBXDSABL 10000 Disable mailbox.
NOBRDCST 20000 Prohibit broadcast.
READSYNC 40000 XON and XOFF on reads.
MECHFORM 80000 Mechanical form feeds.
HALFDUP 100000 Set for half-duplex operation.
MODEM 200000 Set for modem signals.
PAGE FF000000 Page size. Default is 24.
Do not set the CRFILL or LRFILL characteristic as the default in
TTY_DEFCHAR.
Where a condition is false, the value is 0.
The upper byte is the page length. The default characteristics
are 24 lines per page, terminal synchronization, wraparound,
lowercase, scope, and full-duplex.
330 – TTY_DEFCHAR2
TTY_DEFCHAR2 sets a second longword of default terminal
characteristics. The default characteristics are represented
as a code that is derived by summing the following hexadecimal
values:
Characteristic Value (Hex) Function
LOCALECHO 1 Enable local echo terminal logic;
use with the TTY_DEFCHAR NOECHO
characteristic.
AUTOBAUD 2 Enable autobaud detection.
HANGUP 4 Hang up on logout.
MODHANGUP 8 Allow modification of HANGUP without
privileges.
BRDCSTMBX 10 Allow sending of broadcasts to
mailboxes.
XON 20 (No effect in this parameter.)
DMA 40 (No effect in this parameter.)
ALTYPEAHD 80 Use the alternate type-ahead
parameters.
SETSPEED 100 Clear to allow setting of speed
without privileges.
DCL_MAILBX 200 Function reserved for VSI use only.
DECCRT4 400 Terminal is DIGITAL CRT Level 4.
COMMSYNC 800 Enable flow control using modem
signals.
EDITING 1000 Line editing allowed.
INSERT 2000 Sets default mode for insert.
FALLBACK 4000 Do not set this bit with SYSGEN.
DIALUP 8000 Terminal is a dialup line.
SECURE 10000 Guarantees that no process is
connected to terminal after Break
key is pressed.
DISCONNECT 20000 Allows terminal disconnect when a
hangup occurs.
PASTHRU 40000 Terminal is in PASTHRU mode.
SYSPWD 80000 Log in with system password only.
SIXEL 100000 Sixel graphics.
DRCS 200000 Terminal supports loadable character
fonts.
PRINTER 400000 Terminal has printer port.
APP_KEYPAD 800000 Notifies application programs of
state to set keypad on exit.
ANSICRT 1000000 Terminal conforms to ANSI CRT
programming standards.
REGIS 2000000 Terminal has REGIS CRT capabilities.
BLOCK 4000000 Block mode terminal.
AVO 8000000 Terminal has advanced video.
EDIT 10000000 Terminal has local edit
capabilities.
DECCRT 20000000 Terminal is a DIGITAL CRT.
DECCRT2 40000000 Terminal is a DIGITAL CRT Level 2.
DECCRT3 80000000 Terminal is a DIGITAL CRT Level 3.
The defaults are AUTOBAUD and EDITING.
331 – TTY_DEFCHAR3
(Alpha and Integrity servers) TTY_DEFCHAR3 allows a user to set a
bit so that the OpenVMS terminal driver remaps CTRL/H to Delete.
VSI recommends that you not set this bit as a systemwide default.
Characteristic Value (Hex) Function
TT3$M_BS 10 When this bit is set, the OpenVMS
terminal console remaps CTRL/H to
Delete.
For more information, see the SET TERM and SHOW TERM commands in
the VSI OpenVMS DCL Dictionary.
332 – TTY_DEFPORT
TTY_DEFPORT provides flag bits for port drivers. Bit 0 set
to 1 indicates that the terminal controller does not provide
automatic XON/XOFF flow control. This bit should not be set for
VSI Controllers, but it is needed for some foreign controllers.
Currently only the YCDRIVER (DMF32, DMZ32) uses this bit.
The remaining bits are reserved for future use. This special
parameter should be modified only if recommended by VSI.
333 – TTY_DIALTYPE
TTY_DIALTYPE provides flag bits for dialups. Bit 0 is 1 for
United Kingdom dialups and 0 for all others. Bit 1 controls the
modem protocol used. Bit 2 controls whether a modem line hangs
up 30 seconds after seeing CARRIER if a channel is not assigned
to the device. The remaining bits are reserved for future use.
See the OpenVMS I/O User's Reference Manual for more information
about flag bits.
334 – TTY_DMASIZE
TTY_DMASIZE specifies a number of characters in the output
buffer. Below this number, character transfers are performed;
above this number, DMA transfers occur if the controller is
capable of DMA I/O.
TTY_DMASIZE is a DYNAMIC parameter.
335 – TTY_PARITY
TTY_PARITY sets terminal default parity.
336 – TTY_RSPEED
TTY_RSPEED defines the receive speed for terminals. If TTY_
RSPEED is 0, TTY_SPEED controls both the transmit and the receive
speed. Maximum value is 20. This parameter is only applicable for
controllers that support split-speed operations, such as the DZ32
and the DMF32.
337 – TTY_SCANDELTA
TTY_SCANDELTA sets the interval for polling terminals for dialup
and hangup events. Shorter intervals use more processor time;
longer intervals may result in missing a hangup event.
338 – TTY_SILOTIME
TTY_SILOTIME defines the interval at which the DMF32 hardware
polls the input silo for received characters. The DMF32
asynchronous terminal controller can delay the generation
of a single input interrupt until multiple characters have
accumulated in the input silo. TTY_SILOTIME specifies the number
of milliseconds that the characters are allowed to accumulate
prior to the generation of an input interrupt by the hardware.
NOTE
The remainder of this discussion is of interest to customers
who use Digi Edgeport hardware.
TTY_SILOTIME controls latency, trading throughput and system
overhead for latency. The default value for TTY_SILOTIME is 8.
This value is multiplied by 100 and is used as a count of the
number of times to send a query to the device for more data after
a character transmit or receive is performed.
If no input (or no subsequent output) is seen after 800 responses
to the query, the driver stops sending queries to the device and
waits for an input interrupt. Reducing the TTY_SILOTIME value
allows the device to buffer more data, with slightly higher
latency.
Increasing the value of TTY_SILOTIME makes the device more
sensitive to latency but decreases buffering and overall
throughput; it also adds more system and USB overhead. Setting
TTY_SILOTIME to zero causes the driver to send input queries to
the device continually. This setting causes the lowest latency,
the highest system overhead, and the lowest throughput possible.
339 – TTY_SPEED
TTY_SPEED sets the systemwide default speed for terminals. Low
byte is transmit speed, and high byte is receive speed. If high
byte is set to 0, receive speed is identical to transmit speed.
Maximum value is 20. Baud rates are defined by the $TTDEF macro.
340 – TTY_TIMEOUT
TTY_TIMEOUT sets the number of seconds before a process
associated with a disconnected terminal is deleted. The default
value (900 seconds) is usually adequate. Note that using values
for TTY_TIMEOUT greater than one year (value %X01E13380) can
cause overflow errors and result in a disconnected device timing
out immediately.
TTY_TIMEOUT is a DYNAMIC parameter.
341 – TTY_TYPAHDSZ
TTY_TYPAHDSZ sets the size of the terminal type-ahead buffer.
The default value is usually adequate. Do not exceed the maximum
value of 32767 when setting this parameter.
342 – UAFALTERNATE
UAFALTERNATE enables or disables the assignment of SYSUAF
as the logical name for SYSUAFALT, causing all references
to the user authorization file (SYSUAF) to be translated to
SYS$SYSTEM:SYSUAFALT. Use of the normal user authorization file
(SYS$SYSTEM:SYSUAF) can be restored by deassigning the system
logical name SYSUAF. This parameter should be set on (1) only
when the system is being used by a restricted set of users. You
must create a user authorization file named SYSUAFALT prior to
setting UAFALTERNATE to 1.
UAFALTERNATE has the GEN and MAJOR attributes.
343 – USERD1
USERD1 is reserved for definition at the user's site. The
reserved longword is referenced by the symbol SGN$GL_USERD1.
On Alpha and Integrity servers, this symbol is in the
SYS$LOADABLE_IMAGES:SYS$BASE_IMAGE module.
USERD1 is a DYNAMIC parameter.
344 – USERD2
USERD2 is reserved for definition at the user's site. The
reserved longword is referenced by the symbol SGN$GL_USERD2.
On Alpha and Integrity servers, this symbol is in the
SYS$LOADABLE_IMAGES:SYS$BASE_IMAGE module.
USERD2 is a DYNAMIC parameter.
345 – USER3
USER3 is a parameter that is reserved for definition at the
user's site. The reserved longword is referenced by the symbol
SGN$GL_USER3.
On Alpha and Integrity servers, this symbol is in the
SYS$LOADABLE_IMAGES:SYS$BASE_IMAGE module.
346 – USER4
USER4 is a parameter that is reserved for definition at the
user's site. The reserved longword is referenced by the symbol
SGN$GL_USER4.
On Alpha and Integrity servers, this symbol is in the
SYS$LOADABLE_IMAGES:SYS$BASE_IMAGE module.
347 – VAXCLUSTER
VAXCLUSTER controls loading of the cluster code. Specify one of
the following:
Value Description
0 Never form or join a cluster.
1 Base decision of whether to form (or join) a cluster or to
operate standalone on the presence of cluster hardware.
2 Always form or join a cluster.
The default value is 1.
VAXCLUSTER is an AUTOGEN parameter.
348 – VCC_FLAGS
(Alpha only) The static system parameter VCC_FLAGS enables and
disables file system data caching. If caching is enabled, VCC_
FLAGS controls which file system data cache is loaded during
system startup.
Value Description
0 Disables file system data caching on the local node and
throughout the OpenVMS Cluster.
In an OpenVMS Cluster, if caching is disabled on any node,
none of the other nodes can use the extended file cache
or the virtual I/O cache. They can't cache any file data
until that node either leaves the cluster or reboots with
VCC_FLAGS set to a nonzero value.
1 Enables file system data caching and selects the Virtual
I/O Cache. This is the default for VAX systems.
2 Enables file system data caching and selects the extended
file cache. This is the default for Alpha systems.
NOTE
On Integrity servers, the volume caching product
([SYS$LDR]SYS$VCC.EXE) is not available. XFC caching is the
default caching mechanism. Setting the VCC_FLAGS parameter
to 1 is equivalent to not loading caching at all or to
setting VCC_FLAGS to 0.
VCC_FLAGS is an AUTOGEN parameter.
349 – VCC_MAXSIZE
(Alpha and Integrity servers) The static system parameter VCC_
MAXSIZE controls the size of the virtual I/O cache. VCC_MAXSIZE,
which specifies the size in blocks, is 3,700,000 by default.
The virtual I/O cache cannot shrink or grow. Its size is fixed at
system startup.
To adjust the XFC size, use the VCC_MAX_CACHE system parameter.
VCC_MAXSIZE is an AUTOGEN parameter.
350 – VCC_MAX_CACHE
(Alpha and Integrity servers) The dynamic system parameter VCC_
MAX_CACHE controls the maximum size of the extended file cache.
It specifies the size in megabytes. By default, VCC_MAX_CACHE has
a special value of -1 for people who do not want to tune their
systems manually; this value means that at system startup, the
maximum size of the extended file cache is set to 50 percent of
the physical memory on the system.
The extended file cache can automatically shrink and grow,
depending on your I/O workload and how much spare memory
your system has. As your I/O workload increases, the cache
automatically grows, but never to more than the maximum size.
When your application needs memory, the cache automatically
shrinks.
The value of VCC_MAX_CACHE at system startup sets an upper limit
for the maximum size of the extended file cache. You cannot
increase the maximum size of VCC_MAX_CACHE beyond its value
at boot time. For example, if VCC_MAX_CACHE is 60 MB at system
startup, you can then set VCC_MAX_CACHE to 40, which decreases
the maximum size to 40 MB. If you then set VCC_MAX_CACHE to 80,
the maximum size is only increased to 60 MB, the value set at
system startup.
Note that VCC_MAX_CACHE is a semi-dynamic parameter. If you
change its value, you must enter the DCL command SET CACHE/RESET
for any changes to take effect immediately. Otherwise, it might
take much more time for the changes to take effect.
If you are using the reserved memory registry to allocate
memory permanently, you must set the VCC$MIN_CACHE_SIZE entry
in the reserved memory registry to a value less than or equal to
VCC_MAX_CACHE at system startup time.
For instructions on setting permanent memory allocations for the
cache, see the VSI OpenVMS System Manager's Manual.
VCC_MAX_CACHE is a DYNAMIC parameter.
351 – VCC_MAX_IO_SIZE
(Alpha and Integrity servers) The dynamic system parameter VCC_
MAX_IO_SIZE controls the maximum size of I/O that can be cached
by the extended file cache. It specifies the size in blocks. By
default, the size is 127 blocks.
Changing the value of VCC_MAX_IO_SIZE affects reads and writes to
volumes currently mounted on the local node, as well as reads and
writes to volumes mounted in the future.
If VCC_MAX_IO_SIZE is 0, the extended file cache on the local
node cannot cache any reads or writes. However, the system is
not prevented from reserving memory for the extended file cache
during startup if a VCC$MIN_CACHE_SIZE entry is in the reserved
memory registry.
VCC_MAX_IO_SIZE is a DYNAMIC parameter.
352 – VCC_MAX_LOCKS
(Alpha and Integrity servers) VCC_MAX_LOCKS is a special
parameter reserved for VSI use only. Extended file cache will
use this parameter in future versions.
353 – VCC_PAGESIZE
(Alpha and Integrity servers) VCC_PAGESIZE is a special parameter
reserved for VSI use only. Extended file cache will use this
parameter in future versions.
354 – VCC_READAHEAD
(Alpha and Integrity servers) The dynamic system parameter VCC_
READAHEAD controls whether the extended file cache can use read-
ahead caching. Read-ahead caching is a technique that improves
the performance of applications that read data sequentially.
By default VCC_READAHEAD is 1, which means that the extended file
cache can use read-ahead caching. The extended file cache detects
when a file is being read sequentially in equal-sized I/Os, and
fetches data ahead of the current read, so that the next read
instruction can be satisfied from cache.
To stop the extended file cache from using read-ahead caching,
set VCC_READAHEAD to 0.
Changing the value of VCC_READAHEAD affects volumes currently
mounted on the local node, as well as volumes mounted in the
future.
Readahead I/Os are totally asynchronous from user I/Os and only
take place if sufficient system resources are available.
VCC_READAHEAD is a DYNAMIC parameter.
355 – VCC_RSVD
(Alpha and Integrity servers) VCC_RSVD is a special parameter
reserved for VSI use only. Extended file cache will use this
parameter in future versions.
356 – VCC_WRITEBEHIND
(Alpha and Integrity servers) VCC_WRITEBEHIND is reserved for VSI
use only. Extended file cache will use this parameter in future
versions.
357 – VCC_WRITE_DELAY
(Alpha and Integrity servers) VCC_WRITE_DELAY is reserved for VSI
use only.
358 – VHPT_SIZE
(Integrity servers only) VHPT_SIZE is the number of kilobytes to
allocate for the virtual hash page table (VHPT) on each CPU in
the system:
o 0 indicates that no VHPT is allocated.
o 1 indicates that OpenVMS is to choose a default size that is
appropriate for your system configuration.
If a VHPT is created, the smallest size is 32KB. The VHPT_SIZE
must be a power of 2 KB in size. If the number specified is not
a power of 2, OpenVMS chooses a VHPT size to use for your system
that is close to the number specified.
If insufficient memory is available during system startup,
OpenVMS might choose a smaller size for the VHPT of each CPU.
A summary of possible values for VHPT_SIZE is in the following
table:
Value Description
0 Do not create a VHPT on each CPU.
1 (default) OpenVMS chooses a VHPT of an appropriate size for
each CPU.
n Create a VHPT of nKB for each CPU, where n is a power of
2 that is 32 or greater. (The maximum value, however, is
platform-dependent.)
359 – VIRTUALPAGECNT
On VAX systems, VIRTUALPAGECNT sets the maximum number of virtual
pages that can be mapped for any one process. A program is
allowed to divide its virtual space between the P0 and P1 tables
in any proportion.
If you use SYS$UPDATE:LIBDECOMP.COM to decompress libraries
and the VIRTUALPAGECNT setting is low, make sure you set the
PGFLQUOTA field in the user authorization file to at least twice
the size of the library.
At installation time, AUTOGEN automatically sets an appropriate
value for VIRTUALPAGECNT. The value depends on the particular
configuration-the type and number of graphics adapters on the
system, if any exist. You cannot set VIRTUALPAGECNT below the
minimum value required for your graphics configuration.
Because the VIRTUALPAGECNT setting supports hardware address
space rather than system memory, do not use the value of
VIRTUALPAGECNT that AUTOGEN sets to gauge the size of your page
file.
Starting with OpenVMS Version 7.0, VIRTUALPAGECNT has been an
obsolete parameter on Alpha systems. Note, however, that the
parameter remains in existence on Alpha and Integrity servers
for compatibility purposes and has a default and maximum value of
%X7FFFFFFF. SYSBOOT and AUTOGEN enforce this default value.
VIRTUALPAGECNT has the AUTOGEN, GEN, and MAJOR attributes.
360 – VMS1-8
VMSD1, VMSD2, VMSD3, VMSD4, VMS5, VMS6, VMS7, and VMS8 are
special parameters reserved for VSI use. VMSD1 through VMSD4 are
DYNAMIC.
361 – VOTES
VOTES establishes the number of votes an OpenVMS Cluster member
system contributes to a quorum.
VOTES has the AUTOGEN attribute.
362 – WBM_MSG_INT
WBM_MSG_INT is one of three system parameters that are available
for managing the update traffic between a master write bitmap
and its corresponding local write bitmaps in an OpenVMS Cluster
system. The others are WBM_MSG_UPPER and WBM_MSG_LOWER. These
parameters set the interval at which the frequency of sending
messages is tested and also set an upper and lower threshold that
determine whether the messages are grouped into one SCS message
or are sent one by one.
In single-message mode, WBM_MSG_INT is the time interval in
milliseconds between assessments of the most suitable write
bitmap message mode. In single-message mode, the writes issued by
each remote node are, by default, sent one by one in individual
SCS messages to the node with the master write bitmap. If
the writes sent by a remote node reach an upper threshhold
of messages during a specified interval, single-message mode
switches to buffered-message mode.
In buffered-message mode, WBM_MSG_INT is the maximum time a
message waits before it is sent. In buffered-message mode, the
messages are collected for a specified interval and then sent
in one SCS message. During periods of increased message traffic,
grouping multiple messages to send in one SCS message to the
master write bitmap is generally more efficient than sending each
message separately.
The minimum value of WBM_MSG_INT is 10 milliseconds. The maximum
value is -1, which corresponds to the maximum positive value that
a longword can represent. The default is 10 milliseconds.
WBM_MSG_INT is a DYNAMIC parameter.
363 – WBM_MSG_LOWER
WBM_MSG_LOWER is one of three system parameters that are
available for managing the update traffic between a master
write bitmap and its corresponding local write bitmaps in an
OpenVMS Cluster system. The others are WBM_MSG_INT and WBM_MSG_
UPPER. These parameters set the interval at which the frequency
of sending messages is tested and also set an upper and lower
threshold that determine whether the messages are grouped into
one SCS message or are sent one by one.
WBM_MSG_LOWER is the lower threshold for the number of messages
sent during the test interval that initiates single-message mode.
In single-message mode, the writes issued by each remote node
are, by default, sent one by one in individual SCS messages to
the node with the master write bitmap. If the writes sent by
a remote node reach an upper threshhold of messages during a
specified interval, single-message mode switches to buffered-
message mode.
The minimum value of WBM_MSG_LOWER is 0 messages per interval.
The maximum value is -1, which corresponds to the maximum
positive value that a longword can represent. The default is
10.
WBM_MSG_LOWER is a DYNAMIC parameter.
364 – WBM_MSG_UPPER
WBM_MSG_UPPER is one of three system parameters that are
available for managing the update traffic between a master
write bitmap and its corresponding local write bitmaps in an
OpenVMS Cluster system. The others are WBM_MSG_INT and WBM_MSG_
LOWER. These parameters set the interval at which the frequency
of sending messages is tested and also set an upper and lower
threshold that determine whether the messages are grouped into
one SCS message or are sent one by one.
WBM_MSG_UPPER is the upper threshold for the number of messages
sent during the test interval that initiates buffered-message
mode. In buffered-message mode, the messages are collected for a
specified interval and then sent in one SCS message.
The minimum value of WBM_MSG_UPPER is 0 messages per interval.
The maximum value is -1, which corresponds to the maximum
positive value that a longword can represent. The default is
100 seconds.
WBM_MSG_UPPER is a DYNAMIC parameter.
365 – WBM_OPCOM_LVL
WBM_OPCOM_LVL controls whether write bitmap system messages are
sent to the operator console. Possible values are shown in the
following table:
Value Description
0 Messages are turned off.
1 The default; messages are provided when write bitmaps are
started, deleted, and renamed, and when the SCS message
mode (buffered or single) changes.
2 All messages for a setting of 1 are provided plus many
more.
WBM_OPCOM_LVL is a DYNAMIC parameter.
366 – WINDOW_SYSTEM
WINDOW_SYSTEM specifies the windowing system to be used on a
workstation. Specify one of the following values:
Value Description
1 Load the DECwindows Motif for OpenVMS workstation
environment.
2 Load the UIS workstation environment.
WINDOW_SYSTEM is a DYNAMIC parameter.
367 – WLKSYSDSK
(Alpha and Integrity servers) WLKSYSDSK is used by various
bootstrap components to determine if the system disk should be
treated as though it is write-locked. This parameter is used
primarily to allow OpenVMS to boot from a CD.
368 – WPRE_SIZE
WPRE_SIZE represents the number of pages to be allocated to
accommodate WatchPoint Recovery Entries (WPRE) on the Watchpoint
Driver.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
WPRE_SIZE is a DYNAMIC parameter.
369 – WPTTE_SIZE
WPTTE_SIZE is the number of entries that the WPDRIVER creates in
the WatchPoint Trace Table.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
WPTTE_SIZE is a DYNAMIC parameter.
370 – WRITABLESYS
WRITABLESYS controls whether system code is writable. This
parameter is set (value of 1) for debugging purposes only.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
371 – WRITESYSPARAMS
On Alpha and Integrity servers, WRITESYSPARAMS indicates that
parameters are modified during SYSBOOT and are written out to
ALPHAVMSSYS.PAR by STARTUP.COM.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
WRITESYSPARAMS is a DYNAMIC parameter.
372 – WSDEC
Increasing the value of this parameter tends to increase the
speed with which working set limits are decreased when the need
arises.
On Alpha and Integrity servers, WSDEC specifies the number of
pagelets by which the limit of a working set is automatically
decreased at each adjustment interval (which is quantum end). At
a setting of 35, for example, the system decreases the limit of a
working set by 35 pagelets each time a decrease is required.
WSDEC has the AUTOGEN, DYNAMIC, and MAJOR attributes.
373 – WSINC
Decreasing the value of this parameter tends to reduce the speed
with which working set limits are increased when the need arises.
Normally, you should keep this parameter at a high value because
a rapid increase in limit is often critical to performance.
On Alpha and Integrity servers, WSINC specifies the number of
pagelets by which the limit of a working set is automatically
increased at each adjustment interval (which is quantum end). At
a setting of 150, for example, the system increases the limit of
a working set by 150 pagelets each time an increase is required.
On Alpha and Integrity servers, the default value is 2400 512-
byte pagelets (150 8192-byte Alpha and Integrity server pages).
A value of 0 for WSINC disables the automatic adjustment of
working set limits for all processes. Limits stay at their base
values. You can disable the automatic adjustment of working
set limits on a per-process basis by using the DCL command SET
WORKING_SET.
WSINC has the DYNAMIC and MAJOR attributes. On Alpha and
Integrity servers, WSINC also has the AUTOGEN attribute.
374 – WSMAX
WSMAX sets the maximum number of pages on a systemwide basis for
any working set. WSMAX is calculated as a quarter of the first
32 MB plus a sixteenth of the memory from 32 to 256 MB, plus a
sixty-fourth of the memory (if any) above 256 MB.
This is intended to assist managers of systems that host large
numbers of users whose working sets are not large. Systems whose
user bases consist of a small number of users (or processes)
that require large amounts of physical memory (for example,
simulations) might need to set MIN_WSMAX to a value that
satisfies the requirements of those processes.
WSMAX has the AUTOGEN, GEN, and MAJOR attributes.
375 – XQPCTL2
XQPCTL2 controls improved concurrency. The default value of
XQPCTL2 is 1, which turns on improved concurrency. Setting
XQPCTL2 to 0 turns off improved concurrency. This parameter
affects local access to the extent and file ID caches.
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
376 – XQPCTLD1
XQPCTLD1 controls multithreading, which can be used only
by PATHWORKS servers. The default value of XQPCTLD1 is 8,
which enables multithreading. Setting XQPCTLD1 to 0 disables
multithreading,
This special parameter is use by VSI and is subject to change. Do
not change this parameter unless VSI recommends that you do so.
377 – ZERO_LIST_HI
(Alpha and Integrity servers) ZERO_LIST_HI is the maximum number
of pages zeroed and put on the zeroed page list. This list is
used as a cache of pages containing all zeros, which improves the
performance of allocating such pages.
ZERO_LIST_HI has the AUTOGEN and DYNAMIC attributes.