Re: (RE): Calculating LIOs

From: Tanel Põder <tanel.poder.003_at_mail.ee>
Date: Fri, 13 Aug 2004 22:35:18 +0300
Message-ID: <06a101c4816c$aa6edda0$71849fd9@porgand>

2 small comments after I re-read my post (of course after hitting send again):

> abbreviations). So if sessions start hitting a lot of never pinned
prefetch
> blocks, the x$kcbkpfs statistics start to indicate inefficient
prefetching,
> thus causing CBO not to favour it and prefer regular single block reads.

What I meant here is that if lot's of never used prefetched blocks are *aged out*, then the prefetch statistics get worse. If those blocks actually get used, the stats will be ok.

[snip]
> Note that I'm only concluding my last claim, I've not done testing to see
> whether extra branch blocks actually happen - but I don't see any other
way

I meant here "whether extra branch block READS actually happen"...

Tanel.

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Received on Fri Aug 13 2004 - 14:31:06 CDT