PK98861: A HARD LOOP AFTER INTERVAL SWITCH PROCESSING CAN CAUSE HIGH CPU AND HANG IN THE ALLIED ADDRESS SPACE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• A small timing window exists,  whereby a hard loop with PSW
  pointing to module CQMMEMTX with symptoms of high cpu that
  results in an unresponsive system that looks to be hanged.
  This occurs during interval switch processing for the Query
  Monitor Collector.
  

Local fix

• If the problem is encountered, it may be necessary to cancel the
  affected Query Monitor collector (cancel CQMPROD address space)
  to free up the memory.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: Users of DB2 Query Monitor.                  *
  ****************************************************************
  * PROBLEM DESCRIPTION: A small timing window exists,  whereby  *
  *                      a hard loop with PSW pointing to module *
  *                      CQMMEMTX with symptoms of high cpu that *
  *                      results in an unresponsive system that  *
  *                      looks to be hanged. This occurs during  *
  *                      interval switch processing for the      *
  *                      Query Monitor Collector.                *
  ****************************************************************
  * RECOMMENDATION: APPLY the PTF.                               *
  ****************************************************************
  Code has been changed to correct this condition.
  

Problem conclusion

• APPLY the PTF.
  

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:

  UK51576

Modules/Macros

•    CQM#SWTX CQMMEMTX
  

Fix information

• Fixed component name

  DB2 QUERY MONIT

• Fixed component ID

  5655E6701

Applicable component levels

• R230 PSY UK51576

     UP09/11/07 P F911 Ž

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.