Re: System statistics and dbfmbrc
Date: Tue, 8 Jan 2008 15:00:21 +0000
On Jan 8, 2008 2:21 PM, Wolfgang Breitling <centrex_at_centrexcc.com> wrote:
> Quoting Niall Litchfield <niall.litchfield_at_gmail.com>:
> > it's one reason why I'm moving us to collecting
> > (optimizer) stats monthly as a matter of course with more frequent
> > collections the exception driven by proven need. Thanks for your
> > input.
> Contrary to my earlier statement of "sitting on the fence" I think if I
> were in
> a position to make a decision on system statistics strategy I would
> system statistics into a stattab table on a regular basis, maybe hourly if
> workload fluctuates heavily, or maybe longer intervals with the interval
> boundaries coinciding with major workload shifts such as day/online to
> evening/night/batch (in which case 8-hour intervals may make sense) and
> then on
> a weekly or monthly basis review that data and decide whether to update
> dictionary system stats. I would not gather system stats directly into the
What's that old line about "I know you understood what was meant by what I said, but I don't believe that you understand that what I said was not what I meant!"
The word optimizer in my sentence
I'm moving us to collecting (optimizer) stats monthly as a matter of course with more frequent collections the exception driven by proven need.
should have read object. In other words I want to reduce the frequency of * object* stats collections from weekly (or in a couple of cases nightly) to monthly. The bullet point summary in the document that I am writing that prompted this question reads of system statistics
Determine appropriate values for system statistics over a period of a week, review the values every 3-6months.
-- Niall Litchfield Oracle DBA http://www.orawin.info -- http://www.freelists.org/webpage/oracle-lReceived on Tue Jan 08 2008 - 09:00:21 CST