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  • 1.  Why is `onbar -v` so slow?

    Posted Thu February 08, 2024 12:31 PM
    Edited by Dennis Melnikov Fri February 09, 2024 03:01 AM

    Hi,

    While `onbar -b` takes 22 hours, `onbar -r` completes for 30 hours, `onbar -v` runs 7+ days.

    What is wrong with it?



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    Sincerely,
    Dennis
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  • 2.  RE: Why is `onbar -v` so slow?

    Posted Fri February 09, 2024 12:41 AM

    Hi

    because onbar -v is doing a completely different job.
    onbar -b and onbar -r are "simply" reading kind of serial an object (either a dbspace object or a backup object in the storage manager) and the writing it (again either a dbspace object or a backup object). Being able handle more objects in parallel.


    onbar -v does consistency checking. Which is more complex and also needs a "different" reading. I can't be expected that there is enough space to store the whole instance in the file system. So there will be rereads of backup objects and also a lot of reading in files on disk.

    + the checking

    When your instance is huge I would suggest to run verification only on most important dbspaces - or at least one after the other 



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    Hedwig Fuchs
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  • 3.  RE: Why is `onbar -v` so slow?

    Posted Sat February 10, 2024 01:15 PM

    Hi,

    onbar -v runs serial rather than parallel, there is a feature request for this, "Planned for Future Release", upvote it!

    https://ideas.ibm.com/ideas/INFX-I-202

    Regards,
    David.



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    David Williams
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