IT46270: PROCESS APPARENT HANG WHEN QUERYING/USING STORAGE POOL WITH VIRTUAL VOLUMES.

APAR status

• Closed as program error.

Error description

• On the IBM Spectrum Protect Server, any server process querying
  or using a virtual volume storage pool can seem like they are
  hanging.
  The process like an expiration or other virtual volume operation
  or query command is in fact taking a very long time but does not
  hang.
  
  The slowness is seen because it takes a long time to verify if
  using that virtual volume would cause a deadlock.
  
  From the servermon data collection, the following call stack
  example will be seen:
  
  Thread 243703, Parent 243697: AgentThread, Storage 2550368,
  AllocCnt 129 HighWaterAmt 2550368
  tid=1c5f7, ptid=1c1f1, det=1, zomb=0, join=0, result=0,
  sess=82854, procToken=1017, sessToken=82843
  Stack trace:
  0x0900000000697500 _global_unlock_common
  0x09000000006a70f0 pthread_mutex_unlock@AF49_17
  0x000000010000aba0 pkReleaseMutexTracked
  0x0000000100154104 tmRegisterVVolTxn
  0x0000000100959404 smServWrite
  0x0000000101388218 ServWrite
  0x000000010064ade0 AgentThread
  0x0000000100011a70 StartThread
  0x0900000000089214 UNKNOWN
  Holding mutex agentP->mutex (0x1249ea270), acquired at
  pvr.c(13989)
  Holding mutex TMV->mutex (0x1116698b0), acquired at
  tmutil.c(1034)
  Thread context:
  COMMAND: BACKUP STGPOOL
  SCHEDULE_TYPE: ADMIN
  SESSION: sessionNumber
  SCHEDULE_NAME: schedName
  HOSTADDR: hostAddress
  THREAD_TYPE: PROCESS
  PROCESS_DESC: BACKUP STORAGE POOL
  PROCESS_NUMBER: 1017
  SCHEDULED: YES
  HOSTPORT: hostPort
  
  Note: This behavior will not be seen when using virtual volumes
  for database backups.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All IBM Storage Protect server users with virtual volume     *
  * storage pools.                                               *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See error description.                                       *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Apply fixing level when available. This problem is currently *
  * projected to be fixed in levels 8.1.27.100 and 8.2.0. Note   *
  * that this is subject to change at the discretion of IBM.     *
  *                                                              *
  ****************************************************************
  

Problem conclusion

• This problem was fixed.
  Platforms fixed:  AIX, Linux, and Windows.
  
  NOTE:  There is an undocumented option to skip the checking that
  is taking place which should not be enabled if using
  bi-directional virtual volumes.  In addition, the usage of
  virtual volumes for storage pools usage is likely to be
  deprecated in the future.  If this undocumented option is
  required then open a case with the support team.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  TSM SERVER

• Fixed component ID

  5698ISMSV

Applicable component levels