IT25923: IN IBM SPECTRUM CONTROL DB2 CPU USAGE RAISES UP TO 100%

IBM Spectrum Control 5.2.17.1 - Windows Server
IBM Spectrum Control 5.3.1 - Agents
IBM Spectrum Control V5.2.17.1 (November 2018)

APAR status

• Closed as program error.

Error description

• There are 3 to 5 connections (depending on time of snapshots),
  which seems to do permanently run such sql's:
  
  delete from T_RES_VOLUME2EXTENT where VOLUME_ID = ?
  
  insert into T_RES_VOLUME2EXTENT select vc.svid as volume_id,
  v2e.storage_extent_id, v2e.total_num_extents,
  vc.update_timestamp from T_RES_VDISK_COPY2EXTENT v2e,
  T_RES_VDISK_COPY vc where v2e.vdisk_copy_id = vc.vdisk_copy_id
  and vc.is_primary = 1 and vc.svid = ?
  
  Sometimes there are done also some other sql's by other
  connections. However, the above two sql's are the most often
  sql's.
  There is running something in a never ending loop from
  application side.
  
  Those queries are run in a loop for each vdisk coming on an
  event from SVC. This can be changed to running those queries
  only once with a in list instead of single value.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * IBM Spectrum Control users with SVC or Storwize and frequent *
  * changes to vdisk which generate events.                      *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * When processing SVC events triggered by vdisk changes, the   *
  * Spectrum Control code was executing a delete and an insert   *
  * for                                                          *
  * each vdisk.                                                  *
  * Those frequent inserts and deletes was causing DB2 to use    *
  * 100% of CPU time.                                            *
  * The Spectrum Control code was changed so a delete is         *
  * executed                                                     *
  * only when necessary and the couple delete/insert was         *
  * replaced                                                     *
  * by a merge.                                                  *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Apply fix maintenance when available                         *
  ****************************************************************
  

Problem conclusion

• The fix for this APAR is targeted for the following release:
  
  IBM Spectrum Control 5.3.1  |  5.3.1-IBM-SC
  
  ( release target Nov 2018 )
  
  http://www.ibm.com/support/docview.wss?&uid=swg21320822
  
  The target dates for future releases do not represent a formal
  commitment by IBM. The dates are subject to change without
  notice.
  

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

  TPC

• Fixed component ID

  5608TPC00

Applicable component levels