PH05519: WMQ SUBPOOL 2 KEY 8 IS DEPLETED OVER TIME WITH ABEND878 FOR THE MQ CHINIT

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Storage depletion within the CHIN results in varied symptoms
  including CSQV086E REASON 00F3040A where review of storage
  content confirms LE HANC control blocks within Subpool 2
  Key 8 ( in the APAR'd case the full blocks are x8000 bytes long
  comprised of much smaller elements ) Change Team analysis finds
  the issue to be associated with a storage leak while performing
  reverse DNS lookups as part of CHLAUTH processing at channel
  startup time. Externally, this could exhibit with many CSQX519E
  instances, or channel starts that fail due to reaching the
  maximum client instance limit ; with the point that failed
  attempt channel starts are associated with the reported leak.
  .
  Additional keywords:
  SP2 K8 KEY8
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IBM MQ for z/OS Version 9       *
  *                 Release 1 Modification 0.                    *
  ****************************************************************
  * PROBLEM DESCRIPTION: x60 bytes of storage is leaked from the *
  *                      LE heap in the channel initiator        *
  *                      address space when a channel starts     *
  *                      and one or more CHLAUTH ADDRESSMAP      *
  *                      rules specify a hostname rather than an *
  *                      ip adddress.                            *
  *                                                              *
  *                      Over the lifetime of the address space  *
  *                      the leaked storage accumulates, leading *
  *                      to potential performance degradation    *
  *                      and eventual private storage exhaustion *
  ****************************************************************
  During channel startup a list of hostnames associated with
  the conversation's peername is obtained for matching against
  any CHLAUTH rules that specify hostnames.
  During this processing storage is obtained for the control
  blocks containing the hostnames, and this storage should be
  freed on exit from cciTcpGetAllPeerHostnames. However an error
  in the call to free the storage causes it to fail, resulting
  in the storage being leaked.
  
  Additional keywords: addrinfo HANC x60 leak SOS
  

Problem conclusion

• cciTcpGetAllPeerHostnames is changed to correctly free the
  storage.
  

Temporary fix

Comments

APAR Information

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

  PH02753

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

  UI60627

Modules/Macros

• CSQXCRHN
  

Fix information

• Fixed component name

  IBM MQ Z/OS V9

• Fixed component ID

  5655MQ900

Applicable component levels

• R100 PSY UI60627

     UP19/01/26 P F901 ¢

Fix is available

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