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PK95270: IPCONNS GET STUCK IN FREEING/OBTAINING STATE WHEN MAXIMUM SOCKETS IS REACHED

A fix is available

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APAR status

  • Closed as program error.

Error description

  • When maximum sockets is reached and there is a lot of activity
    processing the
    acquiring or releasing of IPCONNs simultaneously, the IPCONNs
    may get stuck in a freeing or
    obtaining state without any other signs of failure.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED: All CICS users.                              *
    ****************************************************************
    * PROBLEM DESCRIPTION: IPCONN left in OBTAINING or FREEING     *
    *                      state during ACQUIRE.                   *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    IPIC connections can be left stuck in OBTAINING or FREEING state
    when socket errors occur during acquire processing, for example
    when CICS reaches MAXSOCKETS.
    
    If one side of the connection has reached resync when a socket
    error occurs on the other side, the resulting socket close
    notification may be lost, leaving that side in OBTAINING waiting
    for a resync flow. It is also possible for the WB session token
    added to the IPIC process queue as a result of a notify request
    to be invalid by the time that the queue entry is actioned.
    
    An additional problem fixed by this apar is an 0C4 abend in
    DFHISIS when using an IPIC connection to TXSeries. The abend
    occurs because DFHISIS attempts to build a UOW header during
    syncpoint processing, but the required data is not available
    when the connection is to a system which is not CICS.
    
    Additional keywords: abend0C4 S0C4 abendS0C4 TX series
                         IPCONN
    

Problem conclusion

  • DFHISRR and DFHISCO have been changed to handle socket close
    notifications during resync and to validate queued WB session
    tokens.
    DFHISIS has been altered to not build a UOW header during
    syncpoint processing when the remote system is not CICS.
    
    The CICS Transaction Server for z/OS Version 4 Release 1
    Trace Entries book, SC34-7013-00, has been updated to add the
    following IS domain trace points:
    
    Point ID|Module |Level| Type                   |Data
    --------+-------+-----+------------------------+--------------
    IS 0542 |DFHISCO|Exc  |PARTNER NOT INSERVICE   |1 ISCO
            |       |     |                        |parameter list
    --------+-------+-----+------------------------+--------------
    IS 0543 |DFHISCO|Exc  |PRIMARY NOT ACQUIRED    |1 ISCO
            |       |     |                        |parameter list
    --------+-------+-----+------------------------+---------------
    IS 0544 |DFHISCO|Exc  |ISSS NOT AVAILABLE      |1 ISCO
            |       |     |                        |parameter list
    --------+-------+-----+------------------------+---------------
    IS 0545 |DFHISCO|Exc  |ISSS NO LONGER OBTAINING|1 ISCO
            |       |     |                        |parameter list
    --------+-------+-----+------------------------+--------------
    IS 0546 |DFHISCO|Exc  |ISSS NO LONGER OBTAINING|1 ISCO
            |       |     |                        |parameter list
    --------------------------------------------------------------
    

Temporary fix

  • FIX AVAILABLE BY PTF ONLY
    

Comments

APAR Information

  • APAR number

    PK95270

  • Reported component name

    CICS TS Z/OS V4

  • Reported component ID

    5655S9700

  • Reported release

    600

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2009-09-02

  • Closed date

    2009-09-25

  • Last modified date

    2009-11-04

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

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

    UK50539

Modules/Macros

  • DESISCO  DESISIS  DESISRR  DESISTRI DESISXF
    DESSOCK  DFHISCO  DFHISCOA DFHISCOM DFHISCOP DFHISCOT DFHISDCC
    DFHISDCD DFHISIS  DFHISISA DFHISISM DFHISIST DFHISRR  DFHISRRA
    DFHISRRM DFHISRRP DFHISRRT DFHISTRI DFHISXF  DFHISXFA DFHISXFM
    DFHISXFT DFHSOCBA DFHSOCBM DFHSOCBT DFHSOCK  DFHSOCKA DFHSOCKJ
    DFHSOCKM DFHSOCKT DFHSOCKV
    

Publications Referenced
SC34701300    

Fix information

  • Fixed component name

    CICS TS Z/OS V4

  • Fixed component ID

    5655S9700

Applicable component levels

  • R600 PSY UK50539

       UP09/10/05 P F910

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.

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Document Information

Modified date:
04 November 2009