IT27752: amqldmpa ending with memory exception (e.g. SIGSEGV) followed byOS pid reuse causes queue manager hang

APAR status

• Closed as program error.

Error description

• The command amqldmpa was executed to dump the state of a queue,
  but it ended with a memory exception (SIGSEGV). Then, a new MQ
  application which started came up with same PID used by the
  amqldmpa.  The application went unresponsive and the queue
  manager did not respond to some of the MQ commands (e.g. dis
  ql) and the following FDCs were generated.
  2018/12/21 23:21:17.020987+7158 amqzxma0  5505234     1 ZX005022
  zxcProcessChildren lrcW_S_FAST_PATH_APP_DEAD
  2018/12/21 23:25:03.092495+7158 amqzlaa0 13959380 60341 XC307100
  xlsRequestMutex    xecL_W_LONG_LOCK_WAIT
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Using MQ fastpath applications including MQ commands (e.g.
  amqldmpa)
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  When an MQ application running in fastpath mode ends abruptly
  the queue manager was not releasing the resources associated
  with the application and this caused the queue manager hang.
  

Problem conclusion

• MQ code has been modified to cleanup the resources associated
  with abruptly ended fastpath applications
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.0 LTS   9.0.0.8
  v9.1 CD    9.1.3
  v9.1 LTS   9.1.0.4
  
  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 MP

• Fixed component ID

  5724H7251

Applicable component levels