Yes. Even with TIMED_STATISTICS=TRUE, relying on *any* statistic with
system-wide scope can waste your time. For a 34-page introduction to the
rationale behind this proposition, see:
http://www.oreilly.com/catalog/optoraclep/chapter/ch01.pdf
Cary Millsap
Hotsos Enterprises, Ltd.
http://www.hotsos.com
Upcoming events:
- Hotsos Clinic 101 in Sydney
- Hotsos Symposium 2004, March 7-10 Dallas
- Visit www.hotsos.com for schedule details...
-----Original Message-----
Wolfgang Breitling
Sent: Thursday, September 04, 2003 6:44 PM
To: Multiple recipients of list ORACLE-L
The number of waits is irrelevant. What matters is the time waited which
in
your case shows 0, but I assume that is because you have not set
timed_statistics to true. Without that the data from v$system_event are
worthless. Cary will probably step in here and tell you that even with
timed_statistics that data is at best of dubious worth.
At 02:49 PM 9/4/2003 -0800, you wrote:
> System-wide Wait Analysis
> for current wait events
>
>
Average
>Event Total Seconds Total
Wait
>Name Waits Waiting Timeouts (in
secs)
>------------- --------- --------- ---------
>-----------
>latch free 1,459 0 1,393
.000
>
>After querying v$system_event my biggest concern is the "latch free"
wait
>event. I understand that latch free is "the process waits for a latch
that
>is currently busy ( held by another process). How can I drill down
and
>find the cause of this? I have a feeling it is about rollback or redo
>logs.
>
>thanks,
>
>
>
>David Ehresmann
>
>--
>Please see the official ORACLE-L FAQ: http://www.orafaq.net
>--
>Author: Ehresmann, David
> INET: [EMAIL PROTECTED]
>
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Wolfgang Breitling
Oracle7, 8, 8i, 9i OCP DBA
Centrex Consulting Corporation
http://www.centrexcc.com
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