IT29679: Queue manager ends with memory exception in rppFindPID in amqrmppa

APAR status

• Closed as program error.

Error description

• Queue manager ended unexpectedly with a memory exception in
  amqrmppa process and
  the following FDCs  were generated.
  
  Probe Id          :- XC130003
  Component         :- xehExceptionHandler
  Program Name      :- amqrmppa
  Major Errorcode   :- STOP
  Probe Type        :- HALT6109
  Probe Description :- AMQ6109S: An internal IBM MQ error has
  occurred
  Arith1            :- 11 (0xb)
  Comment1          :- SIGSEGV: address not mapped((nil))
  
  O/S Call Stack for current thread
  /opt/mqm/lib64/libmqmcs_r.so(xcsPrintStackForCurrentThread+0x3e)
  /opt/mqm/lib64/libmqmcs_r.so(+0x130eea)
  /opt/mqm/lib64/libmqmcs_r.so(PrepareDumpAreas+0xcbf)
  /opt/mqm/lib64/libmqmcs_r.so(xcsFFSTFn+0x1fdc)
  /opt/mqm/lib64/libmqmcs_r.so(xehExceptionHandler+0x705)
  /usr/lib64/libpthread.so.0(+0xf5d0)
  /opt/mqm/lib64/libmqmcs_r.so(xcsRequestMutexSemFn+0x95)
  /opt/mqm/lib64/libmqmr_r.so(rppFindPID+0x22c)
  /opt/mqm/lib64/libmqmr_r.so(rppAdjustPool+0x190)
  /opt/mqm/lib64/libmqmr_r.so(cciResponderThread+0x21c)
  /opt/mqm/lib64/libmqmcs_r.so(+0x1996b6)
  /usr/lib64/libpthread.so.0(+0x7dd5)
  /usr/lib64/libc.so.6(clone+0x6d)
  
  MQM Function Stack
  rppAdjustPool
  rppFindPID
  xcsFFST
  
  Probe Id          :- RM455101
  Component         :- rppFindPID
  Program Name      :- amqrmppa
  Major Errorcode   :- STOP
  Probe Description :- AMQ6109S: An internal IBM MQ error has
  occurred
  
  O/S Call Stack for current thread
  /opt/mqm/lib64/libmqmcs_r.so(xcsPrintStackForCurrentThread+0x3e)
  /opt/mqm/lib64/libmqmcs_r.so(+0x130eea)
  /opt/mqm/lib64/libmqmcs_r.so(PrepareDumpAreas+0xcbf)
  /opt/mqm/lib64/libmqmcs_r.so(xcsFFSTFn+0x1fdc)
  /opt/mqm/lib64/libmqmcs_r.so(xcsFFSTSFn+0x1b3)
  /opt/mqm/lib64/libmqmcs_r.so(+0x125961)
  /opt/mqm/lib64/libmqmcs_r.so(xehExceptionHandler+0x1c5)
  /usr/lib64/libpthread.so.0(+0xf5d0)
  /opt/mqm/lib64/libmqmcs_r.so(xcsRequestMutexSemFn+0x95)
  /opt/mqm/lib64/libmqmr_r.so(rppFindPID+0x22c)
  /opt/mqm/lib64/libmqmr_r.so(rppAdjustPool+0x190)
  /opt/mqm/lib64/libmqmr_r.so(cciResponderThread+0x21c)
  /opt/mqm/lib64/libmqmcs_r.so(+0x1996b6)
  /usr/lib64/libpthread.so.0(+0x7dd5)
  /usr/lib64/libc.so.6(clone+0x6d)
  
  MQM Function Stack
  rppAdjustPool
  rppFindPID
  xcsFFST
  

Local fix

• Set SHARECNV > 1
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users using SVRCONN channels with SHARECNV=1
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  A design limitation of the SVRCONN channel implementation prior
  to MQ 9.1.2 meant that channel resources might be released, then
  subsequently accessed again, causing a memory exception.
  

Problem conclusion

• * Design changes introduced in IBM MQ 9.1.2 have altered the
  implementation of SVRCONN channels such that this issue can no
  longer be encountered in MQ 9.1.2 and higher MQ versions.
  
  * MQ 9.1 LTS code has been modified to fix the problem. When an
  MQ channel is running
     with SHARECNV=1, MQ uses non-shared connection handle. The MQ
  9.1 LTS fix for this APAR uses
     shared connection handles, which requires that MQ fetches the
  connection handle
     details on every MQI call and this may have a slight
  performance overhead.
     Accordingly the fix for this APAR is not enabled by default.
  The fix takes effect when the
     environment variable  AMQ_SVRCONN_SHAREDHCONN_SHARECNV1 is
  set to
     any value(e.g. TRUE or 1) in the environment used to start
  the queue manager and channels.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.1 CD    9.1.2
  v9.1 LTS   9.1.0.5
  
  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

  5724H7271

Applicable component levels