On a database basis, controls which database objects use the OpenVMS Fast I/O and Buffer Objects features.
1 – Description
Use the RMU Set Buffer_Object command to control, on a database basis, which database objects use the OpenVMS Fast I/O and Buffer Objects features.
2 – Format
(B)0[mRMU/Set Buffer_Object root-file-spec [4mCommand[m [4mQualifiers[m x [4mDefaults[m x /Disable=enable-disable-options x See description /Enable=enable-disable-options x See description /[No]Log x Current DCL verify value
3 – Parameters
3.1 – root-file-spec
The root file specification of the database. The default file extension is .rdb.
4 – Command Qualifiers
4.1 – Disable
Disable=enable-disable-options Disables buffer objects for the specified Oracle Rdb buffers. You can specify one or more of the following buffer objects: Page, AIJ, RUJ, and Root. Refer to Buffer Object Control for more information about these keywords. If you specify more than one object, separate the objects with commas, and enclose the list of objects within parentheses.
4.2 – Enable
Enable=enable-disable-options Enables buffer objects for the specified Oracle Rdb buffers. You can specify one or more of the following buffer objects: Page, AIJ, RUJ, and Root. Refer to Buffer Object Control for more information about these keywords. If you specify more than one object, separate the objects with commas, and enclose the list of objects within parentheses. If you specify the Enable and Disable qualifiers for the same buffer object, the Enable option prevails and the buffer object state is enabled for the specified object type. Table 14 Buffer Object Control Object Keyword Logical Name Data PAGE RDM$BIND_PAGE_BUFOBJ_ENABLED pages AIJ AIJ RDM$BIND_AIJ_BUFOBJ_ENABLED output RUJ RUJ RDM$BIND_RUJ_BUFOBJ_ENABLED Root ROOT RDM$BIND_ROOT_BUFOBJ_ENABLED file NOTE If a logical is defined as "1" then the corresponding buffer will be created as an OpenVMS buffer object.
4.3 – Log
Log Nolog Specifies whether the processing of the command is reported to SYS$OUTPUT. Specify the Log qualifier to request log output and the Nolog qualifier to prevent it. If you specify neither, the default is the current setting of the DCL verify switch.
5 – Usage Notes
o The Enable and Disable qualifiers are mutually exclusive. o The RMU Set Buffer_Object command requires exclusive database access; that is, the database cannot be open or be accessed by other users. o Buffer objects are memory resident and thus reduce the amount of physical memory available to OpenVMS for other uses. Buffer object use requires that the user be granted the VMS$BUFFER_ OBJECT_USER rights identifier. The system parameter MAXBOBMEM needs to be large enough to allow all buffer objects for all users to be created. For further information regarding Fast I/O, consult the OpenVMS documentation.
6 – Example
The following example demonstrates enabling ROOT buffer objects and disabling PAGE buffer objects. The RMU /DUMP /HEADER command is used to validate the change. $RMU /SET BUFFER_OBJECT /ENABLE=(ROOT) /DISABLE=(PAGE) MF_PERSONNEL %RMU-I-MODIFIED, Buffer objects state modified %RMU-W-DOFULLBCK, full database backup should be done to ensure futur $ RMU/DUMP/HEAD MF_PERSONNEL . . . - OpenVMS Alpha Buffer Objects are enabled for Root I/O Buffers