Re: A couple of tablespace questions for the experts

Comments interspersed.

Paul Dixon wrote:

>I am planning the design of a new database to host an existing decision
>support sytem, and am trying to decide :-
>
>1] Whether to use Automatic Segment Space Management for tablespaces or to
>use Uniform Extent sizes (as in Howard Rogers tablespace fragmentation
>document) and manually manage the Freelists / Freelist Groups.
>

Use both ... they have nothing to do with each other as in the following example:

CREATE TABLESPACE "DATA_SML" LOGGING
DATAFILE 'c:\oracle\oradata\orabase\datasm01.dbf' SIZE 100M BLOCKSIZE 8192 EXTENT MANAGEMENT LOCAL UNIFORM SIZE 256K SEGMENT SPACE MANAGEMENT AUTO;
>2] Whether there are any siginficant implications from using a small number
>of large datafiles for a tablespace instead of a larger number of smaller
>(i.e. 2 GByte) datafiles.
>

Datafile size is reasonably irrelevant unless you are talking about countless 50M files. Placement is everything.

Assuming you are striping based on what you wrote below ... and I snipped ... I'd be heading for 16GB datafiles on raw devices striped across every spindle I could with the sole exception being the log files.

><snipped>
>
>

HTH

-- 
Daniel Morgan
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