Re: Sort area size

"Joel Garry" <joel-garry_at_home.com> wrote in message news:1105399856.510282.309900_at_c13g2000cwb.googlegroups.com...
>> So theoretically if i increase the size of sort_area_size to more
> then 1MB (say 2MB) will all these sorts fit into memory.
>
> Quite possibly. Don't forget many things use sort segments. Some
> things go through multiple phases, merging when sorting, and might
> benefit a lot from being able to cut down on the number of phases. So
> even if you are at 99%, that other 1% might be something like
> rebuilding indices for a segment that has lots of deletes, or some
> monthly report with rollups. So accelerating that 1% might mean
> allowing a periodic maintenance or reporting window to be much smaller.
>
> Or not.
>
> Testing (and figuring out what really makes the segments) is the only
> way to find out.
>
> http://download-west.oracle.com/docs/cd/B10501_01/server.920/a96533/memory.htm#43396
>
> jg
> --
> @home.com is bogus.
> http://www.powerstrike.net/Tehkan/mamesong.html
>

If there are specific reporting batches which need more memory for sorting, you could always change the sort area size "ad hoc" with "alter session set sort_area_size=...".

Matthias Received on Wed Jan 12 2005 - 16:37:50 CST