PK68914: EYUXC0023S MAXIMUM DATA CACHE LIMIT REACHED. CMAS TERMINATES. QUE DATASPACE FULL

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• If a control block corruption or other problem in a MAS creates
  a loop such that EXEC CICS READ NEXT commands against a CICS
  resource returns the same set of resources repeatedly, the CPSM
  QUE dataspace storage may fill up and cause the CMAS to
  terminate.  This APAR will introduce measures that attempt to
  stop the looping condition from exhausting all the QUE dataspace
  storage as well as get an SVC dump of the regions involved.
  .
  Additional Symptom(s) Search Keyword(s):
  KIXREVRJL
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICSPlex/SM V3R1M0 Users                 *
  ****************************************************************
  * PROBLEM DESCRIPTION: -  If CICS control block corruption in  *
  *                         a MAS causes an EXEC CICS BROWSE     *
  *                         request to loop, the CPSM QUE        *
  *                         dataspaces may fill, resulting in    *
  *                         message:                             *
  *                                                              *
  *                          EYUXC0023S Maximum data cache limit *
  *                                     has been reached for QUE *
  *                                     cache.                   *
  *                                                              *
  *                         This may result in other possible    *
  *                         failures, including termination of   *
  *                         the CMAS to which the MAS is         *
  *                         connected.  If this occurs, message  *
  *                         EYUXC0023S will also be issued by    *
  *                         the CMAS, and will be followed by    *
  *                         message:                             *
  *                                                              *
  *                          EYUXC0024S The CMAS is terminating  *
  *                                     due to a previous error  *
  *                                     with the Cache           *
  *                                     component.               *
  *                                                              *
  *                         Note that EXEC CICS BROWSE requests  *
  *                         are issued by CPSM in a MAS during   *
  *                         MAS initialization for resource      *
  *                         topology data retrieval, and after   *
  *                         initialization in response to EUI,   *
  *                         API, WUI, and RTA requests.          *
  *                                                              *
  *                      -  If an error occurs during resource   *
  *                         topology data retrieval at           *
  *                         initialization of a MAS, the error   *
  *                         may not be reported to the CMAS to   *
  *                         which the MAS is connecting.  This   *
  *                         will allow the MAS to successfully   *
  *                         connect to the CMAS with possible    *
  *                         invalid information.                 *
  *                                                              *
  *                         This may result in security rules    *
  *                         not being followed properly, or in   *
  *                         failures trying to access resources  *
  *                         installed in the MAS through the     *
  *                         EUI, API, WUI, or RTA.               *
  ****************************************************************
  * RECOMMENDATION: After applying the PTF that resolves this    *
  *                 APAR, all CMASes and MASes must be           *
  *                 restarted.  Note that the restarts do not    *
  *                 need to occur at the same time.              *
  ****************************************************************
  -  When CICS control block corruption in a MAS causes an EXEC
     CICS BROWSE request to loop, CPSM will continue to write
     records to the result queue until the QUE dataspaces fill or
     until another error causes the request to fail.
  
  -  Method EYU0NLGT (NLGT) is called during initialization to
     perform resource topology data retrieval.  During this
     process, NLGT will call methods EYU0NLGS (NLGS), EYU0NLGF
     (NLGF), EYU0NLG1 (NLG1) and EYU0NLG4 (NLG4) as part of the
     retrieval process.  If any of these methods encounter an
     error, a OK response is still returned to the CMAS to which
     the MAS is connecting.
  

Problem conclusion

• -  To stop a runaway queue in a MAS from filling the QUE
     dataspaces a cache block limit is being imposed on work
     queues in a MAS.  To effect this change, the following
     updates have been made:
  
     -  The EYURXQSB (QSCB) control block defines an allocated
        CPSM queue structure.  This control block has been updated
        to include a new fullword field, which will be used as a
        counter of cache blocks allocated for the queue.
  
     -  Method EYU0XQCQ (XQCQ) is called to create a CPSM queue.
        When a queue is created, one cache block is allocated to
        the queue.  XQCQ has been updated to set the QSCB block
        count to one.
  
     -  Method EYU0XQPQ (XQPQ) is called to add records to a CPSM
        queue.  If the candidate record will not fit in the cache
        blocks allocated for the queue, XQPQ will call method
        EYU0XQAB (XQAB) to allocate an additional cache block for
        the queue.  XQPQ has been updated to verify if adding the
        new block will exceed the new cache block limit.  If the
        limit will not be exceeded, XQPQ will increment the QSCB
        block count by one.  If the limit will be exceeded, XQPQ
        will fail the request, and issue an exception trace with a
        debug text of "MaxBlks' and a trace point ID of 5.  An
        SVCdump will also be taken.  The title of the dump will be
        similar to the following:
  
          EYU0XZPT Dump,<masjobn>,<masname>,<lpar>,LMAS,
          <tranid>,<tasknum>,TRAC,EYU0XQPQ,<date>,<time>
  
     -  Method EYU0XQAQ (XQAQ) is called to append one CPSM queue
        to another queue.  XQAQ has been updated to verify if the
        result queue will exceed the new cache block limit.  If
        the limit will not be exceeded, XQAQ will update the QSCB
        block count of the result queue with the sum of the block
        counts of the original queues.  If the limit will be
        exceeded, XQAQ will fail the request, and issue an
        exception trace with a debug text of "MaxBlks' and a trace
        point ID of 6.  An SVCdump will also be taken.  The title
        of the dump will be similar to the following:
  
          EYU0XZPT Dump,<masjobn>,<masname>,<lpar>,LMAS,
          <tranid>,<tasknum>,TRAC,EYU0XQAQ,<date>,<time>
  
     -  Method EYU0XQCP (XQCP) is called to copy one queue to a
        new queue.  XQCP has been updated to copy the QSCB block
        count of the source queue to the QSCB block count of the
        target queue.
  
  -  Methods NLGT, NLGS, NLGF, NLG1, and NLG4 have been updated to
     return a Response/Reason of EXCEPTION/METHOD_FAILED to their
     callers if an error occurs during resource topology data
     retrieval.  NLGT will also issue new message:
  
       EYUNL0161E  Resource topology data retrieval failed
  
     Method EYU0TSSC (TSSC), which initiates resource topology
     data retrieval from a CMAS during the Topology Connect
     process, has been updated to ensure the MAS terminates when
     the process fails.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

• -  If CICS control block corruption in
     a MAS causes an EXEC CICS BROWSE
     request to loop, the CPSM QUE
     dataspaces may fill, resulting in
     message:
  
      EYUXC0023S Maximum data cache limit
                 has been reached for QUE
                 cache.
  
     This may result in other possible
     failures, including termination of
     the CMAS to which the MAS is
     connected.  If this occurs, message
     EYUXC0023S will also be issued by
     the CMAS, and will be followed by
     message:
  
      EYUXC0024S The CMAS is terminating
                 due to a previous error
                 with the Cache
                 component.
  
     Note that EXEC CICS BROWSE requests
     are issued by CPSM in a MAS during
     MAS initialization for resource
     topology data retrieval, and after
     initialization in response to EUI,
     API, WUI, and RTA requests.
  
  -  If an error occurs during resource
     topology data retrieval at
     initialization of a MAS, the error
     may not be reported to the CMAS to
     which the MAS is connecting.  This
     will allow the MAS to successfully
     connect to the CMAS with possible
     invalid information.
  
     This may result in security rules
     not be followed properly, or in
     failures trying to access resources
     installed in the MAS through the
     EUI, API, WUI, or RTA.
  
  
  -  When CICS control block corruption in a MAS causes an EXEC
     CICS BROWSE request to loop, CPSM will continue to write
     records to the result queue until the QUE dataspaces fill or
     until another error causes the request to fail.
  
  -  Method EYU0NLGT (NLGT) is called during initialization to
     perform resource topology data retrieval.  During this
     process, NLGT will call methods EYU0NLGS (NLGS), EYU0NLGF
     (NLGF), EYU0NLG1 (NLG1) and EYU0NLG4 (NLG4) as part of the
     retrieval process.  If any of these methods encounter an
     error, a OK response is still returned to the CMAS to which
     the MAS is connecting.
  
  
  -  To stop a runaway queue in a MAS from filling the QUE
     dataspaces a cache block limit is being imposed on work
     queues in a MAS.  To affect this change, the following
     updates have been made:
  
     -  The EYURXQSB (QSCB) control block defines an allocated
        CPSM queue structure.  This control block has been updated
        to include a new fullword field, which will be used as a
        counter of cache blocks allocated for the queue.
  
     -  Method EYU0XQCQ (XQCQ) is called to create a CPSM queue.
        When a queue is created, one cache block is allocated to
        the queue.  XQCQ has been updated to set the QSCB block
        count to one.
  
     -  Method EYU0XQPQ (XQPQ) is called to add records to a CPSM
        queue.  If the candidate record will not fit in the cache
        blocks allocated for the queue, XQPQ will call method
        EYU0XQAB (XQAB) to allocate an additional cache block for
        the queue.  XQPQ has been updated to verify if adding the
        new block will exceed the new cache block limit.  If the
        limit will not be exceeded, XQPQ will increment the QSCB
        block count by one.  If the limit will be exceeded, XQPQ
        will fail the request, and issue an exception trace with a
        debug text of "MaxBlks' and a trace point ID of 5.  An
        SVCdump will also be taken.  The title of the dump will be
        similar to the following:
  
          EYU0XZPT Dump,<masjobn>,<masname>,<lpar>,LMAS,
          <tranid>,<tasknum>,TRAC,EYU0XQPQ,<date>,<time>
  
     -  Method EYU0XQAQ (XQAQ) is called to append one CPSM queue
        to another queue.  XQAQ has been updated to verify if the
        result queue will exceed the new cache block limit.  If
        the limit will not be exceeded, XQAQ will update the QSCB
        block count of the result queue with the sum of the block
        counts of the original queues.  If the limit will be
        exceeded, XQAQ will fail the request, and issue an
        exception trace with a debug text of "MaxBlks' and a trace
        point ID of 6.  An SVCdump will also be taken.  The title
        of the dump will be similar to the following:
  
          EYU0XZPT Dump,<masjobn>,<masname>,<lpar>,LMAS,
          <tranid>,<tasknum>,TRAC,EYU0XQAQ,<date>,<time>
  
     -  Method EYU0XQCP (XQCP) is called to copy one queue to a
        new queue.  XQCP has been updated to copy the QSCB block
        count of the source queue to the QSCB block count of the
        target queue.
  
  -  Methods NLGT, NLGS, NLGF, NLG1, and NLG4 have been updated to
     return a Response/Reason of EXCEPTION/METHOD_FAILED to their
     callers if an error occurs during resource topology data
     retrieval.  NLGT will also issue new message:
  
       EYUNL0161E  Resource topology data retrieval failed
  
     Method EYU0TSSC (TSSC), which initiates resource topology
     data retrieval from a CMAS during the Topology Connect
     process, has been updated to ensure the MAS terminates when
     the process fails.
  

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  PK68912 UK40526

Modules/Macros

•    EYURXQSB EYUTNAM0 EYUUNAEQ EYU0MSIN EYU0NLGF
  EYU0NLGT EYU0NLG1 EYU0NLG4 EYU0TQSR EYU0TSCJ EYU0TSSC EYU0XDH7
  EYU0XLSD EYU0XLST EYU0XQAQ EYU0XQCP EYU0XQCQ EYU0XQPQ
  

Fix information

• Fixed component name

  CPSM CICS 3.1

• Fixed component ID

  5655M1501

Applicable component levels

• R100 PSY UK40526

     UP08/10/10 P F810

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.