Re: Tuning RMAN backup and recovery
Date: Mon, 3 Mar 2008 11:05:34 -0800
On 3/3/08, Don Seiler <don_at_seiler.us> wrote:
> I've read a couple blog posts that say to gather fixed object stats
> weekly, during normal business hours. Another page  also suggested
> gathering dictionary stats as part of the same weekly process.
> Anyone have any thoughts?
>  http://www.toadworld.com/Community/ExpertsBlog/tabid/67/EntryID/135/Default.aspx
> On Mon, Mar 3, 2008 at 9:39 AM, Don Seiler <don_at_seiler.us> wrote:
> > I did have some follow-up questions regarding
> > DBMS_STATS.GATHER_FIXED_OBJECT_STATS().
> > 1. We had noticed that, since gathering the fixed object stats, the
> > time needed to perform a level 0 incremental backup dropped by around
> > 40%. Is this not a coincidence?
> > 2. Is there any schedule or milestone upon which one should re-gather
> > fixed object statistics?
I would recommend that you check out
Upgrading from Oracle Database 9i to 10g: What to expect from the Optimizer
http://www.oracle.com/technology/products/bi/db/10g/pdf/twp_bidw_optimizer_10gr2_0208.pdf This is discussed on page 7 & 8 (Statistics on Dictionary Tables & Statistics on Fixed Objects)
-- Regards, Greg Rahn http://structureddata.org -- http://www.freelists.org/webpage/oracle-lReceived on Mon Mar 03 2008 - 13:05:34 CST