VMS Help  —  RMU72  Set  Buffer Object
    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)0RMU/Set Buffer_Object root-file-spec

  Command Qualifiers                  x Defaults
                                      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
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