IT19286: Memory exceptions seen from amqrmppa process when using SVRCONN channel with SHARECNV(1)

APAR status

• Closed as program error.

Error description

• MQ channel process amqrmppa or amqcrsta randomly failing with
  one or more of the following Failure data capture (FDC) records.
  The
  FDCs generated might be full or partial.
  
  FDC with Probe Id CO000002 and error rrcE_BAD_PARAMETER from
  ccxAllocMem
  FDC with Probe Id CO383000 and error rrcE_BAD_PARAMETER from
  ccxPoolFree
  
  Probe Id          :- CO000002
  Component         :- ccxAllocMem
  Program Name      :- amqrmppa
  Thread            :- 9    RemoteResponder
  Major Errorcode   :- rrcE_BAD_PARAMETER
  ...
  MQM Function Stack
  ccxResponder
  rrxResponder
  ccxReceiveThreadFn
  cciProcessOne
  cciReceiveOne
  ccxReceive
  cciTcpReceive
  ccxAllocMem
  xcsFFST
  
  Probe Id          :- CO383000
  Component         :- ccxPoolFree
  Program Name      :- amqrmppa
  Thread            :- 196    RemoteResponder
  Major Errorcode   :- rrcE_BAD_PARAMETER
  ...
  MQM Function Stack
  ccxResponder
  rrxResponder
  ccxReceiveThreadFn
  cciProcessOne
  cciReceiveOne
  ccxPoolFree
  xcsFFST
  

Local fix

• Alter the value of the SHARECNV attribute from 1, to 2, greater
  than 2, or 0.
  For example, the following statement changes the value to 2:
    ALTER CHANNEL(ChannelName) CHLTYPE(SVRCONN) SHARECNV(2)
  .
  Please check the following URL for details on impact of
  different values in SHARECNV.
  .
  https://www.ibm.com/support/knowledgecenter/SSFKSJ_9.0.0/com.ibm
  .mq.mig.doc/q001660_.htm
  IBM MQ > IBM MQ 9.0.x > IBM MQ > Maintenance and migration >
  IBM MQ migration > Coexistence, compatibility, and
  interoperability > Compatibility between different versions of
  an IBM MQ MQI client and a queue manager >
  MQI client: Default behavior of client-connection and
  server-connection channels
  .
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users using SVRCONN channel with SHARECNV(1) are mostly affected
  by this problem.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  This problem occurred because of a logic error in the internal
  channel buffer management with the queue manager.
  

Problem conclusion

• The IBM MQ queue manager logic has been modified to correct this
  issue  within  internal channel buffer management.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.0 CD    9.0.2
  v9.0 LTS   9.0.0.2
  
  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

• R900 PSY

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