Re: Sometimes the wait interface is useless.
From: Mladen Gogala <no_at_email.here.invalid>
Date: Tue, 10 Nov 2009 19:44:49 +0000 (UTC)
Message-ID: <pan.2009.11.10.19.44.49_at_email.here.invalid>
On Mon, 09 Nov 2009 14:48:21 -0800, joel garry wrote:
Date: Tue, 10 Nov 2009 19:44:49 +0000 (UTC)
Message-ID: <pan.2009.11.10.19.44.49_at_email.here.invalid>
On Mon, 09 Nov 2009 14:48:21 -0800, joel garry wrote:
> http://jamesmorle.wordpress.com/2009/11/09/the-oracle-wait-interface-is-
useless-sometimes-pt/
>
> jg
Of course, all that James Morle says is that there are situations in which the wait interface is not nearly precise enough to do diagnostics. His query spends lots of CPU time, without doing any major waits. Of course, there are tools to deal with that, too: V$SQL monitors SQL by the spent CPU time, there are EXPLAIN PLAN command and 10046 trace which would quickly locate the offending CPU. All that James Morle says is that wait interface is not and must not be the only tool in the DBA arsenal. But then again, Cary Millsap sort of said that in his book, as Morle has mentioned.
-- http://mgogala.freehostia.comReceived on Tue Nov 10 2009 - 13:44:49 CST