From: Craig A. James <cjames@modgraph-usa.com>
To: pgsql-performance@postgresql.org
Subject: Re: Some queries starting to hang
Date: Tue, 06 Jun 2006 10:50:25 -0700
Message-ID: <4485C061.2080206@modgraph-usa.com> (raw)
In-Reply-To: <17426.1149606369@sss.pgh.pa.us>
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Tom Lane wrote:
>>The idea I just had was: why do we need EXPLAIN ANALYZE to run to
>>completion? In severe cases like this thread, we might be able to
>>discover the root cause by a *partial* execution of the plan, as long as
>>it was properly instrumented. That way, the OP might have been able to
>>discover the root cause himself...
>
>
> I don't think that helps, as it just replaces one uncertainty by
> another: how far did the EXPLAIN really get towards completion of the
> plan? You still don't have any hard data.
But at least you have some data, which is better than no data. Even knowing that the plan got stuck on a particular node of the query plan could be vital information. For a query that never finishes, you can't even find out where it's getting stuck.
That's why Simon's proposal might help in some particularly difficult situations.
Regards,
Craig
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To: pgsql-performance@postgresql.org
Cc: cjames@modgraph-usa.com
Subject: Re: Some queries starting to hang
In-Reply-To: <4485C061.2080206@modgraph-usa.com>
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