PH47724: TASK SUSPENDED IN USERWAIT WMCLXSWX PURGED WITH AEXY ABEND

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• In this scenario a running task was running that exceeded it's
  lifetime threshold of 2 minutes as it was in a wait for over an
  hour.  It was suspended in a USERWAIT WMCLXSWX and CICS was not
  able to cancel this task.  The task was eventually purged with
  an AEXY abend resulting in a dump taken by CPSM:
       EYU9XLRV DUMP,masname ,applid,sysid,CMAS,tran,0000123,AEXY
  ,EYU0XXWX,mm/dd/yyyy,hh:mm:ss
  
  The task appeared to be waiting for a lock when it was purged.
  WMCL is the WLM Cross-Plex Lock Facility which deals with
  locking the workload across the PLEX.
  

Local fix

• n/a
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICSPlex SM Users                        *
  ****************************************************************
  * PROBLEM DESCRIPTION: A request from a MAS region to its      *
  *                      CMAS hung waiting for a response.       *
  *                      Eventually the process in the CMAS      *
  *                      ended with a timeout, but did not       *
  *                      return any response to the MAS region   *
  *                      which made the original request.        *
  *                      The process in the MAS had to be        *
  *                      cancelled manually.                     *
  ****************************************************************
  * RECOMMENDATION: After applying the PTF which resolves        *
  *                 PH46410 (V5) or PH47724 (V6), all CMAS       *
  *                 regions should be restarted.                 *
  *                 The restarts may occur in any order.         *
  ****************************************************************
  In the reported problem, a dynamic routing request was issued
  in a MAS regions which had been configured under CPSM as a
  routing region. The workload rules in place were such that this
  request required a new affinity to be created, and therefore
  a WNHP MAL was constructed and transmitted to the local CMAS.
  
  WNHP executed in the CMAS, but required a latch and suspended.
  The stack at this point was XLOP->XLST->WNHP->WSPL->XSWX.
  The latch did not become available, causing the running XLST
  task to exceed its timeout time. When timeout processing was
  next performed (given by TOPOLLINT), the task was purged from
  this suspend.
  
  The process executing in the CMAS was terminated, but due to
  a logic error in method CTBT, no response was returned to the
  MAS. The original routing request in the MAS remained suspended.
  
  The following exception trace points were issued:
   CSLT XLOP LSRT COM EXCP      16 TIMEOUT
   CSLT XLOP LSRT COM EXCP      18 GETCLSTF
   CTBT CTBP XLST COM EXCP      11 TIMEOUT2
  
  A MASRL cache list element in the CMAS was not removed,
  so subsequent errors are possible if the MAS is restarted.
  This would be indicated by a further hang in the MAS region,
  and the following exception trace entries in the CMAS:
   CTBS CTRD LEER COM Excp      8 EXCEPT
   CTRD CLER LEER COM Excp      2 EXCEPT
   CLER XLOP LEER COM Excp      3 EXCEPT
  

Problem conclusion

• Method CTBT (EYU0CTBT) has been updated to ensure that response
  MALs are transmitted back from a CMAS to a MAL, even in the
  case of MALs which have exceeded their alloted timeout time.
  
  Method CSLT (EYU0CSLT) has been updated with additional
  serviceability trace points to assist with future problem
  diagnosis.
  

Temporary fix

Comments

APAR Information

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

  PH46410

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

  UI81774

Modules/Macros

• EYU0CSLT EYU0CTBT
  

Fix information

• Fixed component name

  CICS TS Z/OS V6

• Fixed component ID

  5655YA100

Applicable component levels

• R40M PSY UI81774

     UP22/08/05 P F208

Fix is available

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