IBM Support

PM35301: CONNECTION IS ALWAYS RENEWED WHEN CLIENT AFFINITY IS ENABLED AND IT IMPACTS PERFORMANCE.

Fixes are available

7.0.0.21: WebSphere Application Server V7.0 Fix Pack 21
7.0.0.23: WebSphere Application Server V7.0 Fix Pack 23
7.0.0.25: WebSphere Application Server V7.0 Fix Pack 25
7.0.0.27: WebSphere Application Server V7.0 Fix Pack 27
7.0.0.29: WebSphere Application Server V7.0 Fix Pack 29
7.0.0.31: WebSphere Application Server V7.0 Fix Pack 31
7.0.0.27: Java SDK 1.6 SR13 FP2 Cumulative Fix for WebSphere Application Server
7.0.0.33: WebSphere Application Server V7.0 Fix Pack 33
7.0.0.35: WebSphere Application Server V7.0 Fix Pack 35
7.0.0.37: WebSphere Application Server V7.0 Fix Pack 37
7.0.0.39: WebSphere Application Server V7.0 Fix Pack 39
7.0.0.41: WebSphere Application Server V7.0 Fix Pack 41
7.0.0.43: WebSphere Application Server V7.0 Fix Pack 43
7.0.0.45: WebSphere Application Server V7.0 Fix Pack 45
7.0.0.21: Java SDK 1.6 SR9 FP2 Cumulative Fix for WebSphere
7.0.0.23: Java SDK 1.6 SR10 FP1 Cumulative Fix for WebSphere
7.0.0.25: Java SDK 1.6 SR11 Cumulative Fix for WebSphere Application Server
7.0.0.27: Java SDK 1.6 SR12 Cumulative Fix for WebSphere Application Server
7.0.0.29: Java SDK 1.6 SR13 FP2 Cumulative Fix for WebSphere Application Server
7.0.0.45: Java SDK 1.6 SR16 FP60 Cumulative Fix for WebSphere Application Server
7.0.0.31: Java SDK 1.6 SR15 Cumulative Fix for WebSphere Application Server
7.0.0.35: Java SDK 1.6 SR16 FP1 Cumulative Fix for WebSphere Application Server
7.0.0.37: Java SDK 1.6 SR16 FP3 Cumulative Fix for WebSphere Application Server
7.0.0.39: Java SDK 1.6 SR16 FP7 Cumulative Fix for WebSphere Application Server
7.0.0.41: Java SDK 1.6 SR16 FP20 Cumulative Fix for WebSphere Application Server
7.0.0.43: Java SDK 1.6 SR16 FP41 Cumulative Fix for WebSphere Application Server

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Connection is always renewed when client affinity is enabled.
    This is because WebSphere Application Server checks the return
    code of DB2Connection.alternateWasUsedOnConnect() to see if it
    is true or false. If it is true, WebSphere Application Server
    tries to renew the existing connection.
    
    But DB2Connection.alternateWasUsedOnConnect() always returns
    true when client affinity is enabled. In the end WebSphere
    Application Server always gets true and renews the connection
    so that it impacts performance.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:  All users of IBM WebSphere Application      *
    *                  Server V7.0                                 *
    ****************************************************************
    * PROBLEM DESCRIPTION: Poor performance on failover as         *
    *                      connection is always renewed when       *
    *                      client affinity is enabled.             *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    When client affinity is enabled and there is a failover there
    is a drop in throughput due to the connections being renewed
    with every request. This issue occurs when WebSphere
    Application Server starts using the secondary DB2 server after
    failover. The issue can be seen when using WebSphere
    Application Server with DB2 PureScale.
    

Problem conclusion

  • WebSphere Application Server checks the return code of
    DB2Connection.alternateWasUsedOnConnect().
    If it is true, WebSphere Application Server tries to renew
    the existing connection. When client affinity is enabled, this
    value always returns true in case we are not connecting to the
    primary DB2 instance. The above has been fixed by not renewing
    the connection when client affinity is enabled. The new
    behavior can be enabled via a JVM custom property
    com.ibm.ws.rsadapter.spi.WSRdbDataSource.disablePoolPur
    geIfAffinityEnabled which should be set to true. This can be
    done from the administrative console as mentioned below.
    
    Login to the administrative console > Click Servers > Server
    Types > WebSphere application servers > server_name, and then,
    under Server Infrastructure, click Java and process management
    > Process definition > Java virtual machine > Custom properties
    
    If the custom property is not present in the list of already
    defined custom properties, create a new property, and enter
    com.ibm.ws.rsadapter.spi.WSRdbDataSource.disablePoolPurgeIfAffi
    nityEnabled in the Name field and true in the Value field. If
    the custom property is already defined then change its value
    to true.Restart the server to complete your changes.
    
    The fix for this APAR is currently targeted for inclusion in
    fix pack 7.0.0.21.  Please refer to the Recommended Updates
    page for delivery information:
    http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
    

Temporary fix

Comments

APAR Information

  • APAR number

    PM35301

  • Reported component name

    WEBS APP SERV N

  • Reported component ID

    5724H8800

  • Reported release

    700

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2011-03-22

  • Closed date

    2011-08-19

  • Last modified date

    2011-08-19

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

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

Fix information

  • Fixed component name

    WEBS APP SERV N

  • Fixed component ID

    5724H8800

Applicable component levels

  • R700 PSY

       UP

[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSCVS22","label":"General"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.0","Edition":"","Line of Business":{"code":"","label":""}}]

Document Information

Modified date:
19 August 2011