PH56093: REMOVE MESSAGE QUEUES DURING ABEND

APAR status

• Closed as program error.

Error description

• IHS child process fails with message CRIHS0003E or system
  console reports IPCMSGNIDS shortage
  
  
  KEYWORDS: IPCMSGNIDS
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM HTTP Server on zOS         *
  ****************************************************************
  * PROBLEM DESCRIPTION: If IHS has experienced many crashes and *
  *                      no system IPL, new child processes may  *
  *                      fail due to exhausting IPCMSGNIDS.      *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  Each IHS child process uses a single SysV Message Queue.
  Normally message queues are used for inter-process
  communication, but IHS on zOS uses them in an obscure intra-
  process purpose to integrate with the asyncio() callable
  service.
  On normal termination, the message queue is deleted.
  During an abend, this termination does not happen and the queue
  is leaked. This is because message queues are intended for IPC
  and would normally outlive any individual process.
  

Problem conclusion

• The code was updated in the following ways:
  
  1. Each IHS child process tells the IHS parent process the
  identifier of the  message queue used by each child.
  
  2. The parent already knows when children exit and if it was due
  to a fatal signal. The parent process was modified to remove the
  message queue used by a child that crashes due to SIGSEGV,
  SIGBUS, SIGABRT, and SIGKILL.
  
  
  The fix for this APAR is targeted for inclusion in IBM HTTP
  Server fix packs 8.5.5.25 and 9.0.5.18. For more information,
  see 'Recommended Updates for WebSphere Application Server':
  https://www.ibm.com/support/pages/node/715553
  

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

  WAS IHS ZOS

• Fixed component ID

  5655I3510

Applicable component levels