IV81632: WEBSPHERE MQ CLIENT MAY APPEAR TO BE HUNG OR STOPPED PROCESSING MESSAGES BUT NO ERRORS ARE FOUND ON CLIENT OR QUEUE MANAGE

APAR status

• Closed as program error.

Error description

• A WebSphere MQ client may appear to be hung or stopped
  processing messages
  because messages are building up on the queue.  No error
  message is found on client or queue manage .  A review of a
  trace
  from the queue manager may show bytes sent and bytes received
  are out of step. You will see reference to
  "lpiRC_TRANSACTIONAL_NEXT"  within the trace.
  

Local fix

• Set channel attribute SHARECNV(0) on the channel used by the
  client to bypass the problem
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of asynchronous consume clients may be affected by this
  problem.  If channel send exits are also in use then
  this may increase the likelihood of hitting the problem.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  WebSphere MQ keeps a count of the number of bytes that the
  server has sent to the client, and how many the client has sent
  to the server.  If these numbers get out of step then a
  WebSphere MQ consume thread may enter a state where it can no
  longer consume messages.  This could lead to messages building
  up on the affected queue.
  
  A code error meant that the number bytes that the server had
  sent could be incremented before WebSphere MQ had
  successfully sent those bytes.
  

Problem conclusion

• The code was corrected so that WebSphere MQ would not increment
  the number of sent bytes in the server before it
  had actually sent those bytes to the client.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v7.0       7.0.1.15
  v7.1       7.1.0.8
  v7.5       7.5.0.7
  v8.0       8.0.0.6
  
  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 SOL X86-64

• Fixed component ID

  5724H7231

Applicable component levels