Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1UcVVo-0000Kk-Ue for pgsql-performance@arkaria.postgresql.org; Wed, 15 May 2013 06:48:33 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.72) (envelope-from ) id 1UcVVo-0002cO-Eb for pgsql-performance@arkaria.postgresql.org; Wed, 15 May 2013 06:48:32 +0000 Received: from makus.postgresql.org ([2001:4800:7903:4::125]) by malur.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1UcVVn-0002cE-Bl for pgsql-performance@postgresql.org; Wed, 15 May 2013 06:48:31 +0000 Received: from cl-2390.ham-01.de.sixxs.net ([2001:6f8:900:955::2] helo=feynman.df7cb.de) by makus.postgresql.org with esmtp (Exim 4.72) (envelope-from ) id 1UcVVj-0006Ib-Hm for pgsql-performance@postgresql.org; Wed, 15 May 2013 06:48:30 +0000 Received: from msgid.df7cb.de (lehmann.df7cb.de [IPv6:2001:6f8:10ee:e:136::2]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (Client did not present a certificate) by feynman.df7cb.de (Postfix) with ESMTPSA id 4B08F697BC for ; Wed, 15 May 2013 08:48:24 +0200 (CEST) Date: Tue, 14 May 2013 23:48:20 -0700 From: Christoph Berg To: pgsql-performance@postgresql.org Subject: Re: RT3.4 query needed a lot more tuning with 9.2 than it did with 8.1 Message-ID: <20130515064819.GD704@msgid.df7cb.de> Mail-Followup-To: Christoph Berg , pgsql-performance@postgresql.org References: <20130430112055.GA27525@msgid.df7cb.de> <1583.1367858328@sss.pgh.pa.us> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1583.1367858328@sss.pgh.pa.us> User-Agent: Mutt/1.5.21 (2010-09-15) X-Pg-Spam-Score: 0.8 (/) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-performance Precedence: bulk Sender: pgsql-performance-owner@postgresql.org Re: Tom Lane 2013-05-06 <1583.1367858328@sss.pgh.pa.us> > The newer rowcount estimates are much further away from reality: > > > Unique (cost=1117.67..1118.46 rows=9 width=1115) (actual time=82.646..85.695 rows=439 loops=1) > > > Unique (cost=784205.94..796940.08 rows=145533 width=1061) (actual time=9710.683..9713.175 rows=439 loops=1) > > Has the new DB been analyzed? Maybe you had custom stats targets in > the old DB that didn't get copied to the new one? The new DB was analyzed with various stats targets, including values that were higher that anything we would have used in 8.1. I don't think we had per-table settings in there (the actual DB is now gone for good). Christoph -- cb@df7cb.de | http://www.df7cb.de/ -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance