PM89359: DFHSM0002 030F DOUBLE FREEMAIN OF ICE CONTROL BLOCK AFTER FAILURE WITH OBTAINING THE USER EXTENSION FOR THE ICE

Obtain the fix for this APAR.

APAR status

• Closed as unreproducible.

Error description

• You are running CICS Transaction Server 4.2 and receive the
  following error messages to the console:
  DFHSM0133 CICS is under stress (short on storage above 16MB)
  DFHSM0002 A severe error (code X'030F') has occurred in module
            DFHSMGF.
  and the following meessage to CSMT destination:
  DFHAC2236 Transaction TRAN abend AICJ in program PROGRAM term
        ????.  Updates to local recoverable resources will be
        backed out.
  .
  The focus was understanding the DFHSM0002, Here is the
  corresponding exception trace entry from the dump:
  .
  030F SMGF  *EXC* - Quickcell_freemain_QPF_already_free
              FUNCTION(FREEMAIN) REMARK(ICE)
  The storage being freed is an ICE or interval control element
  that was already freed.  This freemain was issued by
  DFHICP during task termination. DFHICP was called by DFHAPXM
  for RELEASE_XM_CLIENT processing due to field TCAICEAD
  containing an address.
  Backing up and understanding the AICJ processing, I see a
  getmain failure for an Ice User Extention
  .
  SM 030A SMGF  *EXC* - Insufficient_storage_to_satisfy_request -
                        REMARK(SMK7)   ICUS
  .
  The flow of this getmain, is DFHICP, who has an ICE
  control block, calls DFHICUS to create_ice_user_extension.
  DFHICUS calls DFHSMK7 to getmain this extension,
  This getmain fails due to insufficient storage.
  DFHICUS then freemains the ICE control block, but does
  not clear this address from the TCA- field TCAICEAD.
  This later causes the DFHSM0002 error when  DFHICP
  later tries to freemain this same ICE address.
  Additional Symptom(s) Search Keyword(s): DFHSM0002 DFHSM0133
  KIXREVEPH
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All.                                         *
  ****************************************************************
  * PROBLEM DESCRIPTION: DFHSM0002 with error code X'030F' after *
  *                      a short-on-storage situation.           *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The problem presents as:
                                                                 .
  DFHSM0002 A severe error (code X'030F') has occurred in module
            DFHSMGF
                                                                 .
  With a corresponding trace entry of:
                                                                 .
  SM 030F SMGF  *EXC* Quickcell_freemain_QPF_already_free
                                                                 .
  It was caused by DFHICUS FREEMAINing an ICE after it was unable
  to add an extension to it ( in this case due to a Short on
  Storage condition ).  However, the ICE address remained in the
  TCA and was subsequently used in another FREEMAIN attempt at
  task termination which caused the above EXCeption.
                                                                 .
  Keywords: SOS SM0002
  

Problem conclusion

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

• DFHICUS has been modified to clear the ICE address in the TCA
  when it FREEMAINs the ICE which will preclude further FREEMAIN
  attempts.
  

APAR Information

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

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

  UK97734

Modules/Macros

•    DFHICUS
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R700 PSY UK97734

     UP13/09/26 P F309

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.