Next extent with Locally managed tablespace on 9i

From: Norman Dunbar <Norman.Dunbar_at_lfs.co.uk>
Date: Fri, 2 Aug 2002 14:46:08 +0100
Message-ID: <E2F6A70FE45242488C865C3BC1245DA702741FF4@lnewton.leeds.lfs.co.uk>

Christian,

as ever, with Oracle, 'it depends' !

For small objects, keep them in a tablespace with 64K (or 128K) extents. Check them regularly and if they exceed a threshold of extents, move them into a tablespace with say a 1 MB extent.

I'd probably stick with the following :

64KB, 1MB, 8MB 64MB and if I needed anything larger I'd have to consider how big the object is and needs to be.

If you choose a 500 extent threshold, you'll have objects up to the following sizes in each tablespace :

64KB : objects up to 32 MB.
1 MB : Objects up to 500MB.
8 MB : objects up to 4 Gb (assuming the IT worl'd propesity for using

1000 MB as one GB !) or 4000 MB if you like. 64 MB : Objects up to 32,000 MB (32 GB)

The amount of space unused in each table is minimal overall :

Assume you have 10,000 small tables with 1 row each in a 64KB block. That is a grand total of 625 MB which is almost nothing on today's servers.

Cheers,
Norman.

Norman Dunbar
Database/Unix administrator
Lynx Financial Systems Ltd.
mailto:Norman.Dunbar_at_LFS.co.uk

Tel: 0113 289 6265
Fax: 0113 289 3146
URL: http://www.Lynx-FS.com


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-----Original Message-----
From: Christian M. [mailto:cm_at_sdv.fr]
Posted At: Friday, August 02, 2002 1:15 PM Posted To: server
Conversation: Next extent with Locally managed tablespace on 9i Subject: Re: Next extent with Locally managed tablespace on 9i

Ok thanks.

Is there a method to know what is the best value of the extent ( UNIFORM 64K
or more ???? ) Received on Fri Aug 02 2002 - 08:46:08 CDT