X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id D634611F86B9 for ; Tue, 18 Apr 2006 20:15:57 -0300 (ADT) X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Score: 0.301 X-Spam-Level: X-Spam-Status: No, score=0.301 required=5 tests=[AWL=0.301] Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 0OpoqloxdLLD for ; Tue, 18 Apr 2006 20:15:50 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey- Received: from noel.decibel.org (noel.decibel.org [67.100.216.10]) by postgresql.org (Postfix) with ESMTP id 34A7411F7DF9 for ; Tue, 18 Apr 2006 20:15:52 -0300 (ADT) Received: by noel.decibel.org (Postfix, from userid 1001) id 286DE56427; Tue, 18 Apr 2006 18:15:53 -0500 (CDT) Received: (hashcash-sendmail, from uid 1001); Tue, 18 Apr 2006 18:15:52 -0500 Date: Tue, 18 Apr 2006 18:15:52 -0500 From: "Jim C. Nasby" To: Tom Lane Cc: Markus Schaber , pgsql-performance@postgresql.org Subject: Re: merge>hash>loop Message-ID: <20060418231552.GN49405@pervasive.com> References: <1145029009.3422.31.camel@spectre.intellivid.com> <10000.1145031205@sss.pgh.pa.us> <1145033149.3422.41.camel@spectre.intellivid.com> <11035.1145033929@sss.pgh.pa.us> <4444C4CF.2000106@logix-tt.com> <20060418215238.GK49405@pervasive.com> <19388.1145398946@sss.pgh.pa.us> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <19388.1145398946@sss.pgh.pa.us> X-Operating-System: FreeBSD 6.0-RELEASE-p4 amd64 X-Distributed: Join the Effort! http://www.distributed.net User-Agent: Mutt/1.5.11 X-Hashcash: 1:20:060418:tgl@sss.pgh.pa.us::cwE9a1oprI0FqnvH:00000000000000000000 0000000000000000000000002BFs X-Hashcash: 1:20:060418:schabi@logix-tt.com::Z2PzFFb/uEhX8RtI:000000000000000000 0000000000000000000000003Zy+ X-Hashcash: 1:20:060418:pgsql-performance@postgresql.org::/N/lzsroHLkoQ/0e:00000 0000000000000000000000001YGG X-Archive-Number: 200604/408 X-Sequence-Number: 18492 On Tue, Apr 18, 2006 at 06:22:26PM -0400, Tom Lane wrote: > "Jim C. Nasby" writes: > > Actually, if you run with stats_block_level turned on you have a > > first-order approximation of what is and isn't cached. > > Only if those stats decayed (pretty fast) with time; which they don't. Good point. :/ I'm guessing there's no easy way to see how many blocks for a given relation are in shared memory, either... -- Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461