Re: How to manage rolback segments?

From: John Higgins <JH33378_at_deere.com>
Date: Mon, 05 Apr 1999 20:56:15 -0500
Message-ID: <370969BF.ECB69F60@deere.com>

Maybe I don't get it or maybe you made a typo, but: If the 5 rollback segments are only 20 MB then they have not yet grown as big as the 50 MB OPTIMAL.

If you meant that the OPTIMAL is 50 K, then here is an answer: you have set MINEXTENTS to 2, so each rollback segment must have a 10 K initial extent and a 300 K next extent. At some time after a transaction caused a rollback to extend, it would have had the 10K initial extent and some number of 300K extents. When the shrink occurs, it cannot go below 2 MINEXTENTS. In addition, it is possible that the 10K extent is among those given back -- then the MINEXTENTS=2 would mean 2 extents of 300K.

HTH EBR wrote:

> Here they are:
>
> MAXEXTENTS: 500
> MINEXTENTS: 2
> INITIAL: 10K
> NEXT: 300K
> OPTIMAL: 50M
>
> On Sun, 04 Apr 1999 13:02:06 -0500, John Higgins <JH33378_at_deere.com>
> wrote:
>
> >What are the actual parameters for the rollback segments? Initial, next
> >min, max, optimal?
>
> EBR
> ** Please remove the primes to get my real e-mail
Received on Mon Apr 05 1999 - 20:56:15 CDT