PM87206: CPSM MAY ORPHAN TRANSIENT MAL CONTROL BLOCKS.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• CPSM may orphan transient MAL control blocks. In CTSK, if a
  duplicate buffer is processed for some reason, the CMAS may
  issue the following trace entries:
  Task  Mtd  Prev Tran Obj Level Pt-ID  Debug
   1234 CTRP CTSK LNMI COM Excp     17 IgnorBuf
   1234 CTSK CTRD LNMI COM Excp     11 EXCEPT
  When CTSK issues the 11 trace point, it indicates that we tried
  to get a transient MAL but could not. If the trace goes back
  far enough, you may see trace point ID 7 from CTSK, which is
  where the control block originally gets orphaned.  Over time,
  all available transient MALs may get orphaned.
  Additional Symptom(s) Search Keyword(s): KIXREVSVR
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICSPlex SM V5R1M0 Users                 *
  ****************************************************************
  * PROBLEM DESCRIPTION: CPSM communications resources may be    *
  *                      orphaned when an error causes a packet  *
  *                      set from one CMAS to be sent over two   *
  *                      different paths to another CMAS.  If    *
  *                      this occurs often enough, then the pool *
  *                      of resources could be depleted, leading *
  *                      to message EYUCT0105E being issued and  *
  *                      other CPSM communications related       *
  *                      errors.                                 *
  *                                                              *
  *                      The text of message EYUCT0105E will be  *
  *                      similar to the following:               *
  *                                                              *
  *                        EYUCT0105E Transport Services control *
  *                                   block shortage has         *
  *                                   occurred.                  *
  *                                                              *
  *                      Examination of the CMAS's auxtrace      *
  *                      datasets from the time of the message,  *
  *                      will show an exception issued by method *
  *                      EYU0CTSK (CTSK), with a trace point ID  *
  *                      of 11 and a debug text of 'EXCEPT'.     *
  *                      Other exception traces written by CTSK, *
  *                      with a trace point ID of 7 and debug    *
  *                      text of 'EXCEPT', will preceed the      *
  *                      trace point ID 11 traces.  Additional   *
  *                      exception traces written by method      *
  *                      EYU0CTRP (CTRP), with a trace point ID  *
  *                      of 17 and a debug text of 'IgnorBuf',   *
  *                      may also be present.                    *
  ****************************************************************
  * RECOMMENDATION: After applying the PTF that resolves this    *
  *                 APAR, all CMASes must be restarted.  Note    *
  *                 that the restarts do not need to occur at    *
  *                 the same time.                               *
  ****************************************************************
  When a CMAS sends a packet set to another CMAS, it is sent once
  over a fixed communications path, that is defined to the sending
  CMAS as part of a DLST (distribution list of the path from one
  CMAS to another) or a TLST (transmission list of a broadcast to
  all CMASes that are part of the network, a CICSplex or a WLM
  workload) structure.  Every time a CMAS issues a SEND to another
  CMAS, it uses the same DLST.  Everytime a CMAS issues a
  BROADCAST to a specific group of CMASes, it uses the same TLST.
  
  Both the DLST and TLST structures are defined to ensure that
  when a packet set is sent using it, that each CMAS will receive
  the packet set exactly once.  If an error occurs within a DLST
  or TLST where the path to a CMAS is multiply defined, then each
  SEND or BROADCAST using the invalid structure will result in the
  receiving CMAS processing the packet set over multiple paths.
  
  When a packet set is processed by the receiving CMAS, method
  EYU0CTSK (CTSK) builds a message argument list request list
  (MALRL) element that identifies the packet set.  When it has
  completed processing the packet set, the MALRL element is
  removed.  If a packet set is received over multiple paths, then
  it is likely that the second occurrance of the packet set will
  be received before the first packet set is complete.  When this
  occurs CTSK will attempt to build a second MALRL element with
  the same ID.  This will result in CTSK issuing the exception
  trace with a point ID of 7 and a debug text of 'EXCEPT', failing
  the packet set, and orphaning the transient MAL associated with
  the packet set.  There is a finite pool of transient MALs.  If
  they are exhausted, then when CTSK attempts to acquire one, it
  will fail and instead issue message EYUCT0105E and the exception
  trace with point ID 11 and debug text 'EXCEPT'.
  

Problem conclusion

• To resolve the orphaning of transient MALs, CTSK has been
  updated to pass the MAL address to method EYU0CTRC (CTRC) which
  performs cleanup if CTSK fails.
  
  A DLST or TLST should never have multiple paths defined from one
  CMAS to another:
  
  -  To resolve the error that caused an invalid TSLT to be built
     for the problem associated with this APAR, a logic error in
     method EYU0CPRG (CPRG) has been corrected.
  
  -  To identify future occurances of an erroneous DLST or TLST,
     the following additional changes have been made:
  
     -  CTSK has been updated so that if it determines it has
        received the same packet set over multiple paths, it will
        issue new message EYUCT0107E and request a dump of its
        CMAS, and if possible, the originating CMAS where the
        invalid DLST or TLST resides.
  
        If the receiving CMAS can request a dump from the
        originating CMAS, the text of the message will be similar
        to the following:
  
          EYUCT0107E A duplicate packet set was received from CMAS
                     name (<cmasname>).
  
        Additionally, message EYUXZ0902I will be issued indicating
        a dump, code "DupMALRL", has been requested of both the
        receiving and originating CMAS.  The text of the message
        will be similar to the following:
  
          EYUXZ0902I This CMAS has requested dumps, code
                     (DupMALRL), of this CMAS and of CMAS
                     (<origcmasname>).
  
        In the originating CMAS, message EYUXZ0901I will be issued
        indicating a dump, code "DupMALRL", of that CMAS has been
        requested by the receiving CMAS.  The text of the message
        will be similar to the following:
  
          EYUXZ0901I A dump of this CMAS, code (DupMALRL), has
                     been requested by CMAS (<recvcmasname>).
  
        If the receiving CMAS cannot request a dump from the
        originating CMAS, the text of the message will be similar
        to the following:
  
          EYUCT0107E A duplicate packet set was received from CMAS
                     SYSID (<cmassysid>).
  
        The title of the dump in the receiving CMAS will be
        similar to the following:
  
          DupMALRL Dump,jobname,cmasname,lpar,CMAS,tranid,tasknum,
                   TRAC,EYU0CTSK,date,time
  
        If a dump is taken in the originating CMAS, its title will
        be similar to the following:
  
          DupMALRL Dump,jobname,cmasname,lpar,CMAS,XLST,tasknum,
                   TRAC,EYU0XLST,date,time
  
        If this condition occurs, it is likely to continue to
        occur until a change is made in the originating CMAS.  As
        a result, the above message and dump will only be issued
        once during the run of a CMAS.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

APAR Information

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

  PM87106

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

  UK94580

Modules/Macros

• EYU0CPAG EYU0CPRG EYU0CTSK EYU0XZSD EYU9XZP3 EYU9XZP4 EYU9XZPU
  EYUMCCTC EYUMCCTE EYUMCCTK EYUMCXZC EYUMCXZE EYUMCXZK
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R80M PSY UK94580

     UP13/06/11 P F306

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.