OpenVMS Alpha Galaxy Guide
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  10.4  DUMP

  New Qualifier:  /SHARED_MEMORY

  In the event of system crashes, it may be necessary to save
  the contents of some or all of shared memory in addition to
  the memory that is local to the system that has crashed.  This
  will be done either by writing shared memory to the system
  dump file using enhanced system dump code, or as a separate
  step using the DUMP/SHARED_MEMORY command.  This
  can be done either after the failed system reboots, or at any
  time from another instance of OpenVMS in the same com-
  munity.  DUMP/SHARED_MEMORY writes to a separate
  file, not to the system dump file.

  Shared memory included in a system dump file will be
  analyzed with the existing ANALYZE/CRASH_DUMP com-
  mand.  Shared memory dumped separately will be analyzed
  using the new command ANALYZE/SHARED_MEMORY
  (which is the topic of a separate note).

  Syntax Description:

  The format is:  DUMP/SHARED_MEMORY [region_name_
  list] [other_quals]

  where "region_name_list" is a comma-separated list of the
  regions of shared memory to be dumped, a logical name that
  translates to such a list, or*", indicating that all regions in
  shared memory are to be dumped.  If no region name list
  is given, the default is GLX$DUMP_RANGE, which is ex-
  pected to be a logical name that translates to a list of regions
  (or could be the name of a region itself).

  A region name is given in the format:

  region_name [=start_offset {:end_offset | ; number_of_bytes} ]

  If just a region name is given, the entire region is dumped.  If
  a start offset and either an end offset or a number of bytes is
  given, only that range of bytes within the region is dumped.
  If *" is given, it must stand alone.  The default radix for
  start_offset, end_offset, number_of_bytes is hexadecimal.  As
  in SDA, such numbers can include a period to separate the
  upper 32 bits from the lower 32 bits.

  other_quals include the following:

   /ALL_MEMORY  All  shared  memory  is  to  be  dumped  as  a  single
     unit,  regardless  of  whether  it  is  part  of  a
     named  region.  If  /ALL_MEMORY  is  specified,  the
     region  name  list  must  not  be  given.

   /COMPRESSED  The  dump  is  to  be  written  in  a  compressed
     format  (same  algorithm  as  used  in  system  dumps)
   /OUTPUT="file"  The  dump  is  to  be  written  to  the  named  file,
     instead  of  the  default,  which  is
     GLX$SHARED_MEMORY.DMP  in  the  current  default
     directory.
   /SIZE="blocks"  The  size  of  dump  file  to  be  created  initially.
     If  not  given,  a  size  is  calculated.  Either  way,
     the  file  is  truncated  to  the  number  of  blocks
     written  when  the  dump  is  complete.  /SIZE  can
     only  be  specified  if  /OUTPUT  is  also  specified.

   /PHYSICAL  Placeholder  at  this  time.

  Qualifier description:

  The /SHARED_MEMORY qualifier indicates that a
  shared memory dump is to be written.  The new utility
  GLX$DUMP_SHARED_MEMORY.EXE is invoked to write
  the dump.

  Examples:

  1.  $  DUMP/SHARED_MEMORY/ALL_MEMORY
  All  of  shared  memory  is  dumped  to  GLX$SHARED_MEMORY.DMP  in
  the  current  default  directory.

  2.  $  DEFINE/USER  GLX$DUMP_RANGE  REG1,REG2=120000;40000
     $  DUMP/SHARED_MEMORY/COMPRESSED/OUTPUT=TEST
  The  two  regions  REG1  and  REG2  will  be  dumped,  the  former  in  its
  entirety,  but  only  bytes  120000  to  15FFFF  of  the  latter.  The
  dump  will  be  written  in  compressed  format  to  the  file  TEST.DMP
  in  the  current  default  directory.

  3.  $  DUMP/SHARED_MEMORY  *

  All  regions  in  shared  memory  are  dumped  to  GLX$SHARED_MEMORY.DMP  in
  the  current  default  directory.
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