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  • 1.  DBM1 memlimit

    Posted Nov 09, 2021 06:34 PM
    Should the DBM1 memlimit be set to 19T?
    thanks
    Bill

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    williamgiannelliMe
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  • 2.  RE: DBM1 memlimit

    Posted Nov 10, 2021 06:24 AM
    How big are your bufferpools?

    Default now seems to be 19T. It couldn't hurt. But you could run forever with 4T or whatever you're set to now, if your bufferpools aren't in the terabytes-range in total.


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    MarkWieczorkowski...
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  • 3.  RE: DBM1 memlimit

    Posted Nov 10, 2021 07:10 AM
    did the recommendation used to be 16T?

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    williamgiannelliMe
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  • 4.  RE: DBM1 memlimit

    Posted Nov 12, 2021 06:39 AM
    Might have been. IBM's been bumping it up pretty steadily to facilitate the growth of large customers. But it's only a max the region can obtain. You had mentioned previously that you're a smaller shop, so I'd be surprised if your DBM1 needs over the original limit of 4T...you'd need a lot of bufferpool space, FTBs, and other ATB structures to get anywhere NEAR that limit. Making it higher, if you don't need the memory, does nothing.

    Check out RMF, or the IFCID0225 numbers, to see the working size of your DBM1. If you're in the terabyte range, then the MEMLIMIT *may* become an issue for you. If not...just change it whenever you get a chance.


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    MarkWieczorkowski...
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