IBM Support

PI26861: WMQ V710 - HIGH CPU USAGE AFTER A STOP CHINIT COMMAND AND THE CHIN DOES NEVER END. 14/11/24 PTF PECHANGE

A fix is available

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • After a STOP CHINIT command is issued the CHIN address space
    seems to loop and never terminates.
    .
    Additional keywords:
    STOP CHINIT hang hangs hung shutdown
    

Local fix

  • n/a
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED: All users of WebSphere MQ for z/OS Version 7 *
    *                 Release 1 Modification 0.                    *
    ****************************************************************
    * PROBLEM DESCRIPTION: When a STOP CHINIT command is issued,   *
    *                      the channel initiator does not end      *
    *                      and has high CPU usage.                 *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    If a STOP CHINIT command is issued when a server-connection
    channel and a sender channel are running and assigned to the
    same TCB, and rriStopChannel happens to be called first for
    the server-connection channel, a deadlock can occur between
    shut down processing and the sender channel. rriStopChannel,
    when called for a server-connection channel, schedules a
    process to run on the TCB on which the channels are running
    and waits for it to start. At the same time the sender channel
    can go into a loop in rriSendData with MQGETs on the
    transmission queue failing with MQRC_CONNECTION_QUIESCING.
    This loop prevents any other processes from running on the
    TCB, and therefore prevents rriStopChannel from being called
    for the sender channel. The loop in the sender channel
    therefore results in high CPU usage and prevents the channel
    initiator from shutting down.
    

Problem conclusion

  • rriSendData has been updated to immediately set the channel
    status to CLOSING when an MQGET on the transmission queue
    fails with MQRC_CONNECTION_QUIESCING.
    100Y
    CMQXFANL
    CMQXFKWT
    CMQXKTPT
    CMQXKTPU
    CMQXMKMI
    CMQXRSCF
    CMQXRSRV
    CMQXZMUP
    CMQZRFPA
    CSQARFPA
    CSQATELK
    CSQMMTPR
    CSQTELKC
    CSQTOHAK
    CSQUODQL
    CSQUODQU
    CSQURFPA
    CSQXCCIT
    CSQXFCCH
    CSQXFMBY
    CSQXRBLD
    CSQXRCML
    CSQXRFPA
    CSQXRFXC
    CSQXRMTR
    CSQXRRMF
    CSQ7DRPS
    

Temporary fix

Comments

APAR Information

  • APAR number

    PI26861

  • Reported component name

    WMQ Z/OS 7.1 VU

  • Reported component ID

    5655VUE00

  • Reported release

    100

  • Status

    CLOSED PER

  • PE

    YesPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2014-10-02

  • Closed date

    2014-12-17

  • Last modified date

    2016-08-17

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

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

    PI30796 UI23964

Modules/Macros

  • CMQXFANL CMQXFKWT CMQXKTPT CMQXKTPU CMQXMKMI
    CMQXRSCF CMQXRSRV CMQXZMUP CMQZRFPA CSQARFPA CSQATELK CSQMMTPR
    CSQTELKC CSQTOHAK CSQUODQL CSQUODQU CSQURFPA CSQXCCIT CSQXFCCH
    CSQXFMBY CSQXRBLD CSQXRCML CSQXRFPA CSQXRFXC CSQXRMTR CSQXRRMF
    CSQ7DRPS
    

Fix information

  • Fixed component name

    WMQ Z/OS V7

  • Fixed component ID

    5655R3600

Applicable component levels

  • R100 PSY UI23964

       UP15/01/16 P F501 Ø

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.

[{"Business Unit":{"code":"BU054","label":"Systems w\/TPS"},"Product":{"code":"SG19M","label":"APARs - z\/OS environment"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.1","Edition":"","Line of Business":{"code":"","label":""}}]

Document Information

Modified date:
17 August 2016