PI22144: CONTROLLER MEMORY LEAK IN MONITOR SUBTASK IF MONQ BECOMES FULL.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• If the TWSz MONITORING SUBTASK is active (MONOPTS init statement
  coded) but unable to communicate with the REMOTE MONITORING
  AGENT (messages EQQMH18E and EQQMH19E), the EQQMONDS and MONQ
  may become completely full.  This condition exposes a memory
  leak in the MON subtask which over an extended period can cause
  multiple controller problems.
  .
  These problems may include.
  1) Message EQQX261E RSN21 in the ISPF DIALOGS when trying to
     update operation status in the CP
  2) Inability to obtain requested LSR buffers for CP/SI data sets
  3) Internal controller enqueue lockup with multiple tasks stuck
     waiting for CP lock while the MON subtask is holding that
     lock and is itself waiting for completion of a TCP WRITE to
     the REMOTE MONITORING TASK.  This Enqueue lockup basically
     stops all TWSz activities related to scheduled workload, and
     can only be resolved by stopping and restarting the CONTROLER
     started task.
  4) While the Controller is in the ENQUEUE LOCKUP described above
     it is not possible to run any CP or LTP batch jobs.
  

Local fix

• The problems described above occur when the Controller has run
  for an extended time with the MON subtask unable to communicate
  with the remote agent.  If the CONTROLLER is stopped and
  restarted, the immediate symptoms are corrected, and TWSz will
  function normally again until the memory leak consumes too much
  storage.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All TWS for z/OS users running external      *
  *                 monitor                                      *
  *                 FUNCTION=MAJOR                               *
  ****************************************************************
  * PROBLEM DESCRIPTION: Memory leak can occurs when the TWSz    *
  *                      monitoring subtask queue becomes full.  *
  ****************************************************************
  * RECOMMENDATION: APPLY THE PTF FIXING THIS APAR               *
  ****************************************************************
  If the TWSz monitoring subtask is active but unable to
  communicate with the remote monitoring agent, the EQQMONDS
  and MONQ may become completely full. This condition exposes
  a memory leak.
  

Problem conclusion

• When the MONQ events queue is full the storage allocated
  for the monitoring events is not released.
  Now this area is freed.
  500Y
  510Y
  600Y
  910Y
  920Y
  EQQZMTSK
  

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:

  UI21006 UI21007 UI21008 UI21009 UI21010

Modules/Macros

• EQQZMTSK
  

Fix information

• Fixed component name

  TIV WRKLD SCHD

• Fixed component ID

  5697WSZ01

Applicable component levels

• R500 PSY UI21006

     UP15/01/27 P F501

• R510 PSY UI21007

     UP15/01/27 P F501

• R600 PSY UI21008

     UP15/01/27 P F501

• R910 PSY UI21009

     UP15/01/27 P F501

• R920 PSY UI21010

     UP15/01/27 P F501

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.