Re: RBSs not extending, ORA-01555

<tandym_at_hotmail.com> schreef in berichtnieuws 8d2g4s$5jn$1_at_nnrp1.deja.com...
> Hi all,
>
> Recently we have been having problems with the rollback segments -
> first it was - unable to extend rollback segment...
>
> So, I shrank all of the RBSs down to the minimum (they were created
> without the optimal clause) and figured that would be that. Well, not
> too long afterward, we started receiving 'snapshot too old' errors.
>
> I figured that it was having an overwrite problem, and so created 15
> more rollback segments, hoping that would fix it. Nope. I
> consistently receive this error every couple of days. Its not always
> the same rollback segment, its not always the same user and its not
> always the same program/process. All of the RBSs are STILL at their
> shrunk (or original, for those recently created) size - in other words,
> they have not extended out at all. They are all at 10 mb with the
> ability to grow to 100 mb. The new ones I have created start out at 50
> mb and grow to 200. None of them have grown at all.
>
> We are using Oracle 7.3.3.6 on a OpenVMS 7.1 box.
> Does anyone have a clue? Thanks in advance...
>
> sonya
>
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.

You are receiving this error just because you shrank the rollback segments. Oracle maintains read consistency information in the rollback segments, this is not considered a transaction, hence the rollback segments won't extend because the read consistency info doesn't fit anymore. They will wrap round and end in ora-1555, as you already experienced. Creating 15 extra rollback segments has nothing to do with it, as a transaction never switches from one rollback segment to another.

Regards,

Sybrand Bakker, Oracle DBA Received on Wed Apr 12 2000 - 00:00:00 CDT