Re: dbms_stats.gather_system_stats
- From: Connor McDonald <hamcdc@xxxxxxxxxxx>
- To: ORACLE-L@xxxxxxxxxxxxx
- Date: Wed, 8 Sep 2004 01:52:39 +0100 (BST)
Although I'd argue that (more often than not) even slightly dubious system
stats may more than
make up for deficiencies in init.ora settings, the most common one being
db_file_multiblock_read_count. I've seen many a place where the requested
value (ie init.ora) and
the observed value (from system stats) are wildly different.
Cheers
Connor
--- Wolfgang Breitling <breitliw@xxxxxxxxxxxxx> wrote:
> Gathering system stats gives the optimizer more information about the
> current workload mix and the capabilities of the system ( cpu speed, IO
> performance). In general this should lead to better access plans and better
> performance and I have heard that people have had good success with it.
> However, any changes that impact the optimizer should be tested thoroughly
> because there could be nasty surprises. If you have a mixed workload, e.g.
> OLTP during the day and batch during off-hours, you should have separate
> system statistics for each workload and switch them in as appropriate.
>
=====
Connor McDonald
Co-author: "Mastering Oracle PL/SQL - Practical Solutions"
ISBN: 1590592174
web: http://www.oracledba.co.uk
web: http://www.oaktable.net
email: connor_mcdonald@xxxxxxxxx
Coming Soon! "Oracle Insight - Tales of the OakTable"
"GIVE a man a fish and he will eat for a day. But TEACH him how to fish,
and...he will sit in a boat and drink beer all day"
------------------------------------------------------------
___________________________________________________________ALL-NEW Yahoo!
Messenger - all new features - even more fun! http://uk.messenger.yahoo.com
--
To unsubscribe - mailto:oracle-l-request@xxxxxxxxxxxxx&subject=unsubscribe
To search the archives - //www.freelists.org/archives/oracle-l/
Other related posts:
