1.- To know when is the time to increase size and number of rbs: use
utlbstat/utlestat during peek hours and take a look of the columns =
WAITS and
WRAPS.
2.- To use set transaction use rbs in a PL/SQL you should use the =
package
DBMS_TRANSACTION.USE_ROLLBACK_SEGMENT(<rbs>)
Regards.
> -----Mensaje original-----
> De: Rajesh Dayal [SMTP:Rajesh_at_ohitelecom.com]
> Enviado el: Mi=E9rcoles 28 de Junio de 2000 12:03
> Para: Multiple recipients of list ORACLE-L
> Asunto: Performance Issue (Urgent ????)
>=20
> Hi DBAs
> Could someone point me what could be the performance impact of
> increasing the rollback segment size? Recently I had increased the =
RBS
> size from 100K initial extent to 1M initial extent and optimal size =
60M
> (Oracle 7.3.4/DEC Unix with a maxextents limit of 121). So that some =
of
> the batch jobs (that are fired on normal time) don't fail because of
> space problem.=20
> I could have used "SET TRANSACTION USE RBS ", but the job is
> fired through a PL/SQL block. I tried without luck to make the PL/SQL
> block, use one specific RBS (bigger one). So I had to increase all =
the
> RBS storage settings. Now the performance has dipped down a lot :~((
> I had a glance of report.txt (utl*stat) in the begining I found
> that the DB Buffer Cache hit ratio has come down to 65%.=20
> So whether the size of RBS can really have impact on DB Buffer
> Cache Hit Ratio ?? If yes then how? Else other possible reasons ??
> I am attatching some other points of botheration from
> report.txt.. Could someone pin-point the bottleneck area and refer =
me
> to some URL/Sites that explain report.txt ??
>=20
> Thanks a Lot...
> Rajesh
Received on Wed Jun 28 2000 - 15:46:04 CDT