IT15806: Memory leak in amqrmppa process when SSL / TLS connection fails and is rapidly retried

APAR status

• Closed as program error.

Error description

• Using IBM MQ Version 7.5.0.6, a memory leak was observed
  in the amqrmppa process, when a SSL / TLS channel connection
  fails in a loop, for example due to an expired certificate in
  the key database of the queue manager. In this case the channel
  security handshake failed and the channel would reconnect and
  fail again and continue to do so in a loop. As a result the
  amqrmppa process continued to grow in memory consumption (swap
  space).
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users using SSL channels with applications often connecting and
  disconnecting to/from the queue manager.
  
  Scenarios in which SSL connections repeatedly fail and are
  rapidly retried, for example due to a configuration error, are
  more likely to experience this issue.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  This problem occurred due to a timing window which could cause
  internal resources to fail to be cleaned up when multiple
  threads were starting and ending SSL sessions concurrently.
  

Problem conclusion

• The MQ queue manager has been updated to correctly clean up the
  internal resources in this scenario, preventing the memory leak.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v7.5       7.5.0.8
  v8.0       8.0.0.6
  v9.0 CD    9.0.4
  v9.0 LTS   9.0.0.1
  
  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

  WMQ BASE MULTIP

• Fixed component ID

  5724H7241

Applicable component levels