PH53752: DSWC WAIT AFTER 6.1 UPGRADE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• A timer (TI) task is handling a Socket TIMEOUT. The TI task
  (00008) locks the S8TLSHS chain using DSWR
  Function(GET_RESOURCE) but fails to perform a RELEASE_RESOURCE
  to free the lock and hence DSWC SSL socket counts exceed 90% of
  the MAXSSLTCBS SIT value.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS users                               *
  ****************************************************************
  * PROBLEM DESCRIPTION: All CICS WEB tasks attempting to        *
  *                      perform TLS handshakes hang due to no   *
  *                      S8TLSHS resource slots being available. *
  ****************************************************************
  A task makes an EXEC CICS WEB OPEN call using a CLIENT URIMAP to
  a host name specifying HTTPS and with a SOCKETCLOSE value.
  No data is sent so no TLS handshake is performed. The socket is
  subsequently returned to the pool as a result of an EXEC CICS
  WEB CLOSE or at end of task.
  
  The socket is not reused within the SOCKETCLOSE interval causing
  a Timer (TI) task to run to remove the socket from the pool and
  close it.  When this logic runs the required cleanup of the
  S8TLSHS slot is not performed.
  
  If this happens many times all S8TLSHS slots can be leaked,
  causing any subsequent tasks which want to perform TLS
  handshakes to suspend indefinitely in a DSWC S8TLSHS wait.
  

Problem conclusion

• DFHSOMG has been changed so that when a socket is removed from
  the socket pool during close processing a check is made to see
  if the socket held an S8TLSHS slot and, if so, release the slot.
  

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:

  UI93398

Modules/Macros

• DFHSOPL
  

Fix information

• Fixed component name

  CICS TS Z/OS V6

• Fixed component ID

  5655YA100

Applicable component levels

• R400 PSY UI93398

     UP23/10/02 P F309

Fix is available

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