OA63726: 3-WAY DEADLOCK INVOLVING SHCDS LISTDS

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• In the reported case, a deadlock between a SHCDS LISTDS command
  and two OPEN threads occurred that lead to an ABEND30D.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All VSAM RLS users issuing SHCDS LISTDS                      *
  * command while multiple opens or CICS                         *
  * subsytems are registering with RLS.                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * Deadlock between SHCDS LISTDS                                *
  * command and OPENs/register subsystem                         *
  * can lead to an ABEND30D.                                     *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  A three way deadlock happens between SHCDS LISTDS command and
  two open/register subsystem threads:
  1. IGWLYSBC latch obtained during open/register
  2. IGWLYSUB latch obtained during open/register
  3. SPM latch obtained SHCDS LISTDS command
  The deadlock can occur in both open and register subsystem
  path.
  D sms,smsvsam,diag(c)
  15.27.56 SYSTEM1           IEE932I 972
  IGW343I VSAM RLS DIAG STATUS (V.01)
  |----RESOURCE---| |------ WAITER ------| |--HOLDER---| ELAPSED
   TYPE        ID    JOB NAME ASID   TASK   ASID   TASK     TIME
  -------- -------- -------- ---- -------- ---- -------- ---------
  LATCH    7D50EF88 SMSVSAM  000A 007D56C0 000A 007D5950  02:17:53
  LATCH    7D110BF0 SMSVSAM  000A 007D5950 000A 007D1B58  02:18:08
  LATCH    7D112270 SMSVSAM  000A 007D1B58 000A 007D56C0  02:18:15
        DESCRIPTION: IGWLYSUB - SHM OBJECT POOL
  

Problem conclusion

• New ENQ SYSZSCM1 major name IGWLISTDS minor name has been added
  to serialize OPEN/register with SHCDS LISTDS command.
  

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:

  UJ93966 UJ93975 UJ93976

Modules/Macros

• IDAVSTAI IGWSRTE3 IGWLNI10 IDAVCREG IGWLNI12 IGWLNMAT IGWLDREM
  IDAV194A
  

Fix information

• Fixed component name

  VSAM REC LEV SH

• Fixed component ID

  5695DF122

Applicable component levels

• R310 PSY UJ93966

     UP23/11/29 P F311

• R250 PSY UJ93976

     UP23/11/29 P F311

• R240 PSY UJ93975

     UP23/11/29 P F311

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.