IBM Support

PI62169: CONCURRENT MULTIPLE LOGIN AND OPERATIONS CAUSE SIGNIFICANT SLOWDOWN TO CLEARQUEST WEB ON WINDOWS

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • On ClearQuest web, attempting concurrent login and other
    operations cause significant slowdown, lock timed out error
    and/or eventual hang.
    
    The refcount mutexes appear to be causing significant slowdown
    on Windows.
    
    In the cqrpc dumps, many threads are in CreateMutex which
    suggests there may be some kind of synchronization occurring in
    mutex creation (and destruction).
    
    This is the cause since Win32 will check to see if the mutex
    already exists before trying to create it. So it has to lock on
    the entire set of mutexes. Since on Windows, mutexes are system
    wide (and exist across processes), this may also add some
    synchronization across processes.
    
    Note,
    On UNIX, the mutexes appear not to be causing any performance
    issues.
    ClearQuest 8.0.1.10 TestFix4 and later is affected by this
    defect.
    
    Steps to reproduce;
    1) Start independent browser sessions about 40 depending on the
    load performance
    2) Click login on each browser session moving one by one
    manually
    3) Extract Query folder one by one
    4) Run query on each browser
    
    Repeat 3) - 4), if possible.
    
    The login prompt and loading process slow down, hang or respond
    error.
    SystemOut.log starts recording lock timed out error and then
    thread hang message.
    

Local fix

  • None
    
    Easing login or workspace load by removing query folders and
    shortcut, limiting the number of concurrent user login in a
    certain amount of time might help if not completely.
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * ClearQuest Web                                               *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * ClearQuest Web might get sluggish on Windows after many      *
    * users logged in.                                             *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    

Problem conclusion

  • A fix is available in ClearQuest 9.0.0.1
    A change was made to eliminate the slow down on ClearQuest Web.
    

Temporary fix

Comments

APAR Information

  • APAR number

    PI62169

  • Reported component name

    CLEARQUEST WIN

  • Reported component ID

    5724G3600

  • Reported release

    801

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2016-05-10

  • Closed date

    2016-06-13

  • Last modified date

    2016-06-13

  • 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

    CLEARQUEST WIN

  • Fixed component ID

    5724G3600

Applicable component levels

  • R801 PSY

       UP

[{"Business Unit":{"code":"BU053","label":"Cloud \u0026 Data Platform"},"Product":{"code":"SSSH5A","label":"Rational ClearQuest"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"801","Line of Business":{"code":"LOB36","label":"IBM Automation"}}]

Document Information

Modified date:
16 October 2021