Re: Forcing a table into memory
Date: 1996/04/18
Message-ID: <31768CD0.5C08_at_fred.net>#1/1
Mike wrote:
>
> sahmad_at_mfa.com (Saad Ahmad) wrote:
>
> >Krister D. Ungerboeck (kunger_at_pop.interaccess.com) wrote:
> >> Is it possible to force a table into memory and ensure that Oracle
> >> doesn't swap it out?
> >In oracle 7.2.x and up (also 7.1.6 i think )
> >alter table xxxx cache;
>
> But be aware that that only means that after the first full table scan
> the table's blocks will be put at the bottom of the Least Recently
> Used (LRU) list. Meaning that it's much *less* likely to be swapped
> out of the DB buffer cache. If you do enough other processing
> without referencing the cached table it's still possible for it to be
> flushed from the buffer... At least that's what I remember from the
> 7.1 and 7.2 "New features" class...
>
> Mike
>
There's one more thing that's crude but effective.... If you've got the cpu cycles and the io loads aren't too bad you can have a job run every so often that touches all the rows. That's how we pinned tables in the v6 days. It still doesn't gaurantee it's pinned but it shure increases the odds.
-Joel Received on Thu Apr 18 1996 - 00:00:00 CEST