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.