IT41012: IBM MQ agent process (amqzlaa0) terminates unexpectedly in queuefull scenario

APAR status

• Closed as program error.

Error description

• The scenario is like below:
  - Dead letter queue is defined, and full.
    - Queue manager events are going to a QALIAS naming a topic
  object as target.
    - One or more subscribers exist for this topic, but their
  destination queues are full.
    - Queue manager has relevant events enabled, and something
  happens that generates such an event.
  
  In the above scenario, when an event is generated, a queue
  manager agent process (amqzlaa0) terminates unexpectedly, a core
  file may be created from the process, and FDCs are created,
  including one like this:
  
  amqzxma0 ZX005035 zxcProcessChildren zrcX_AGENT_DEAD
  

Local fix

• Drain the Subscriber destination queue(s) and/or dead letter
  queue.
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users who are in the scenario described.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  Within the MQPUT processing in the queue manager agent
  (amqzlaa0) an infinite recursion was attempted, leading to
  exhaustion of stack space for the thread.
  

Problem conclusion

• Protection has been added to the IBM MQ code so that the
  infinite recursion is not attempted.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.1 LTS   9.1.0.12
  v9.2 LTS   9.2.0.7
  v9.3 LTS   9.3.0.2
  v9.x CD    9.3.1
  
  The latest available maintenance can be obtained from
  'WebSphere MQ Recommended Fixes'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'WebSphere MQ
  Planned Maintenance Release Dates'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
  ---------------------------------------------------------------
  

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

  IBM MQ BASE M/P

• Fixed component ID

  5724H7261

Applicable component levels