X-Original-To: pgsql-benchmarks-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 2793F329E8E; Wed, 6 Oct 2004 15:16:50 +0100 (BST) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 12764-06; Wed, 6 Oct 2004 14:16:44 +0000 (GMT) Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by svr1.postgresql.org (Postfix) with ESMTP id D2716329E64; Wed, 6 Oct 2004 15:16:43 +0100 (BST) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.13.1/8.13.1) with ESMTP id i96EGeKS025577; Wed, 6 Oct 2004 10:16:40 -0400 (EDT) To: =?ISO-8859-1?Q?=22Alban_M=E9dici_=28NetCentrex=29=22?= Cc: pgsql-benchmarks@postgresql.org, pgsql-performance@postgresql.org Subject: Re: [PERFORM] stats on cursor and query execution troubleshooting In-reply-to: <4163C5C3.3030304@fr.netcentrex.net> References: <4163C5C3.3030304@fr.netcentrex.net> Comments: In-reply-to =?ISO-8859-1?Q?=22Alban_M=E9dici_=28NetCentrex=29=22?= message dated "Wed, 06 Oct 2004 12:15:31 +0200" Date: Wed, 06 Oct 2004 10:16:39 -0400 Message-ID: <25576.1097072199@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.0 tagged_above=0.0 required=5.0 tests= X-Spam-Level: X-Archive-Number: 200410/2 X-Sequence-Number: 19 =?ISO-8859-1?Q?=22Alban_M=E9dici_=28NetCentrex=29=22?= writes: > I'm looking for the statistic of memory, CPU, filesystem access while=20 > executing some regular SQL query, and I want to compare them to > same kind of results while executing a cursor function. I think your second query is finding all the disk pages it needs in kernel disk cache, because they were all read in by the first query. This has little to do with cursor versus non cursor, and everything to do with hitting recently-read data again. regards, tom lane