Re: system table space highly fragmanted

In article <387C63E1.41AE1559_at_synergy-infotech.com>,   Anurag Minocha <anurag_at_synergy-infotech.com> wrote:
> Hi ,
> My system tablespace is highly fragmanted.
> Somewhere I read that deffered rollback segments use the system
> tablespace, and because of this the systrem table space gets
fragmanted.
>
> I use a shutdown abort every day to take backup's Can this create
> deffered rollback segments.
>
> -How do i fix the highly fragmanted system table space.,
> -While database creation stage how can i make sure that the system
> tablespace doesn't get fragmanted.
>
> Any help will be appreciated.
>
> Thanks
> Anurag
>

Cold backups taken after a shutdown abort are no good unless you are re- starting the database in restricted session and allowing Oracle to perform instance recovery then shutting it down normal before performing the backup. You potentially have uncommited transactions to be resolved.

As a general rule, DBA's do not worry about system tablespace fragmentation since dictionary objects that are being used are normally cached in the library cache so the fragmentation should not matter, per Oracle. I have seen where Oracle support has said it is acceptable to modify the sql.bsq file to add the initial extent storage parameter before creating the database where the data will be imported from an existing database.

It should also be acceptable to alter the next extent size for the base tables, where you know you will use the space, just as the Oracle repository product, designer, installation instructions tell you to change the next and pctincrease parameters for the tables used to store package code (since the product contains a lot of packages).

Before you change anything related to sys I suggest you talk to support or at least read the Concepts, DBA Admin, and Installation manuals cover to cover.

When it comes to sys owned items Oracle support is a little funny. Oracle support will tell you how to move the sys.aud$ table out of the system tablespace (the instructions are in the Oracle DBA Admin Class student notes) but they will also tell you that it is unsupported. --
Mark D. Powell -- The only advice that counts is the advice that  you follow so follow your own advice --

Sent via Deja.com http://www.deja.com/
Before you buy. Received on Wed Jan 12 2000 - 10:59:08 CST