Re: Problem with growing rollback segment

Vladimir

Shrinking to OPTIMAL is done when:

1. Another extent is about to be allocated i.e. when Oracle fills an extent, before another extent is allocated, it will attempt to shrink toward OPTIMAL

AND 2. There are free extents of unused space in the rollback segment.

There are two important things to be aware of here. Firstly, if there is more than 30 Mb of active extents in your rollback segment, the shrink will not go back to OPTIMAL because of this. it will free up some space, but obviously can't touch the active extents. Secondly, both conditions 1 and 2 need to be met before any shrinking is done.

Another possibility is that the combination of INITIAL and MINEXTENTS is greater than 30 Mb. Also, by the way you've worded your question it appears you're only using the one rollback segment? You may want to add more.

HTH. Pete

vladoh_at_my-deja.com wrote:

> Hi.
> Could someone help me. I have this problem.
> I use Oracle7.3 and have set my rollback segment
> to optimal size 30MB. There are three applications
> (two are only selecting rows and one (Inserter) is
> also inserting data (1min freq)). My rollback
> segment sometimes is at 30MB but sometimes grows
> above 30MB (to 800MB or more...) and doesn't drops
> again to 30MB
> Inserter then doesn't success to insert data in
> 1minute frequency. Where is the problem? Inserter
> uses transactions. There are also some triggers
> that insert, update and also delete data.
>
> thanx for help
> Vladimir Hirner
>
> Sent via Deja.com http://www.deja.com/
> Share what you know. Learn what you don't.

--
Regards

Pete

Received on Fri Jul 16 1999 - 11:17:34 CDT