PH52830: DISPLAY QUEUE COMMAND CAN CAUSE MANY SQL FETCHES IF THERE ARE A LOT OF SHARED QUEUES.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Client has noticed the number of SQL calls on a particular QMGR
  seems to have increased after migrating to V9.2.
  They noticed SQL calls increasing on 1 QMGR.
  When DISPLAY QUEUE runs, it first searches for any matching
  private queues, and then for any matching shared queues.
  In this case there were many shared queues and a high
  frequency number of Display Queue commands.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IBM MQ for z/OS Version 9       *
  *                 Release 2 Modification 0 and                 *
  *                 Release 3 Modification 0.                    *
  ****************************************************************
  * PROBLEM DESCRIPTION: The DISPLAY QUEUE command causes high   *
  *                      DB2 usage when issued in a queue        *
  *                      sharing group (QSG) environment.        *
  *                      The high usage is due to a large number *
  *                      of FETCH requests from plan CSQ5L920 or *
  *                      CSQ5L930                                *
  ****************************************************************
  When DISPLAY QUEUE is issued on a queue manager in a queue
  sharing group, and the QSGDISP specified or defaulted includes
  shared disposition queues, each shared queue defined in the QSG
  is fetched from DB2 and processed to determine if it matches the
  requested object name(s).
  

Problem conclusion

• DISPLAY QUEUE processing have been updated to locate shared
  queues using in storage data, avoiding the need to fetch each
  record from DB2.
  

Temporary fix

Comments

• ×**** PE23/10/18 FIX IN ERROR. SEE APAR PH57646  FOR DESCRIPTION
  

APAR Information

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

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

  UI93711 UI93712

Modules/Macros

• CSQM1DQU CSQMDQUE
  

Fix information

• Fixed component name

  IBM MQ Z/OS V9

• Fixed component ID

  5655MQ900

Applicable component levels

• R200 PSY UI93712

     UP23/10/10 P F310 ¢

• R300 PSY UI93711

     UP23/10/10 P F310 ¢

Fix is available

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