From: Tom Lane <tgl@sss.pgh.pa.us>
To: Rolf Østvik <rolfostvik@yahoo.no>
Cc: pgsql-performance@postgresql.org
Subject: Re: Worse perfomance on 8.2.0 than on 7.4.14
Date: Sun, 31 Dec 2006 12:11:28 -0500
Message-ID: <4049.1167585088@sss.pgh.pa.us> (raw)
In-Reply-To: <200612311233.10201.rolfostvik@yahoo.no>
References: <200612311233.10201.rolfostvik@yahoo.no>
Rolf =?iso-8859-1?q?=D8stvik?= <rolfostvik@yahoo.no> writes:
> I have a simple query which uses 32ms on 7.4.14 and 1015ms on 8.2.0.
There's something awfully strange about that 8.2 plan --- if it knew
that it'd have to scan all of uut_result_subset (which it should have
known, if the stats were up-to-date), why did it use an indexscan
rather than a seqscan? Are you sure you haven't tweaked any parameters
you didn't tell us about, such as setting enable_seqscan = off?
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, rolfostvik@yahoo.no
Subject: Re: Worse perfomance on 8.2.0 than on 7.4.14
In-Reply-To: <4049.1167585088@sss.pgh.pa.us>
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