Re: Buffer Pool KEEP -- NOT keeping !!

it might be worth checking that
the buffers have actually loaded
into the KEEP pool -

    set_ds on x$bh maps to addr on x$kcbwds     set_id on x$kcbwds will be between lo_setid and hi_setid     in v$buffer_pool for the relevant buffer pool

--

Jonathan Lewis
Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk

Allen Hayden wrote in message <87ero9$1th$1_at_nntp1.atl.mindspring.net>...
>
>My understanding was that objects with properties
>assigned the Buffer_Pool ='KEEP' would be permanently
>held in that KEEP cache.
>
>I created a KEEP pool of 200M with the goal of having
>this large index permanently cached there. For the
>most part it works great!
>
>BUT there's a little mystery...
>
>I created a procedure that would force a full index
>scan to prime that index into the KEEP cache. After i
>run the priming procedure i check the cache to see how many
>buffers are used by the object using this SQL script
>
>SQL> l
> 1 select obj,count(*)
> 2 from sys.xbh
> 3 where obj =2821
>SQL> /
>
> OBJ COUNT(*)
>--------- ---------
> 2821 14506
>
>The Mystery is that some 10 minutes later if i run the
>same script, its shows a LOWER buffer count. If all buffers
>that are thrown into KEEP cache are supposed to be pinned there
>then why are my pinned buffers for this object less on the
>2nd query.
>
>FYI: I have only one object in the entire database that is
>assigned to the KEEP cache. I'm running this on an NT box
>with 458M of RAM using v8.0.5.
>
>Any comments would be appreciated.
>Thanks
>Jason
>
>
>
>
>
>
>
>
Received on Fri Feb 04 2000 - 14:17:46 CST