Re: Pad temp extents a few bytes larger than sort_area_size?

It is not the size of the memory sort area that is being copied ... it is the size of the transaction. The size is likely too large ... and likely irrelevant unless you have some horrible shortage of disk space. I would normally use something between 64K and 256K but then that is because I have a sense of the size of the transactions.

Daniel Morgan

Alan wrote:

> Hello,
>
> I'm currently working on a statement to create a temporary tablespace
> on my 8i DB. Here is what I have so far:
>
> CREATE TEMPORARY TABLESPACE temp
> TEMPFILE '/u2/oracle/data/B/tempb.dbf' size 200m reuse
> EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1048576;
>
> I picked a UNIFORM SIZE of 1M because my
> SORT_AREA_SIZE = 1048576
>
> Am I wise to set the UNIFORM SIZE to 1048576?
>
> If Oracle needs to do a disk sort it will want to copy data from
> my memory sort area into TABLESPACE TEMP.
>
> When it does this copy, will it be happy to see an extent
> which matches the SORT_AREA_SIZE exactly?
>
> Or would the copy go quicker if I setup temp so each extent
> is padded a few bytes larger than SORT_AREA_SIZE?
>
> A variation on this question is this:
> Should each extent by a multiple of SORT_AREA_SIZE?
>
> If yes, should the extent be 'padded' by a few bytes?
>
> Alan
Received on Sat Mar 23 2002 - 15:05:02 CST