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  1. #1
    Join Date
    Jan 2009
    Posts
    33

    Unanswered: db2 9.7 fp5 issues

    Hello All,
    running db2 9.7fp5 on AIX 6.1. Automatic table maintenance with statistics was turned on. Reorg was off. And monitoring switches were switched on. And we had some performance issues where one of the batches which had java/cobol code which in general runs for 3 hours took around 14 hours. raised a pmr and was told that the automatic table maintenance is causing the issue, it is continuously looping and causing this performance issue and were told to switch it off. I just wanted to know if any of you are also facing the same issue as I thought even when the program ran for 3 hours teh first day the auto maintenance was on. This is more like an information i thought of sharing and also knowing whether this is a known bug.

    Regards,
    Sharath

  2. #2
    Join Date
    May 2003
    Location
    USA
    Posts
    5,737
    Real DBA's don't use DB2 Automatic Maintenance. There are a variety of problems, as you have noted.

    Automatic Maintenance is basically a marketing driven feature to convince managers who are DBMS purchase decision makers that DB2 has a lot of automatic features that don't require them to hire highly qualified DBA's, and not as many DBA's as before. It doesn't work very well as you have found out, and usually causes more problems than it solves.

    Also, turning on all your monitor switches can add a noticeable load to the system, especially if the system is being stressed.
    M. A. Feldman
    IBM Certified DBA on DB2 for Linux, UNIX, and Windows
    IBM Certified DBA on DB2 for z/OS and OS/390

  3. #3
    Join Date
    Jan 2009
    Posts
    33

    db2 9.7fp5 issues

    Hello marcus,
    You are right with auto maintenance which can be triggered using cron or schedulers. But if we do not have monitor switches and in case we encounter some performance issues we will not have data to analyse the issues.However I also believe on a well tested and designed system you do not require monitor switches to be on and auto maint to be turned on.
    But not all systems are perfect.

    Regards,
    Sharath

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