Received: from localhost (maia-4.hub.org [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id BB2ED9F9F0E for ; Sun, 3 Dec 2006 00:05:20 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-new, port 10024) with ESMTP id 71589-06 for ; Sun, 3 Dec 2006 00:05:16 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by postgresql.org (Postfix) with ESMTP id 7E8DF9F9429 for ; Sun, 3 Dec 2006 00:05:16 -0400 (AST) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.13.6/8.13.6) with ESMTP id kB345Cx9012527; Sat, 2 Dec 2006 23:05:14 -0500 (EST) To: "Alexandru Coseru" cc: "Heikki Linnakangas" , pgsql-performance@postgresql.org Subject: Re: Regex performance issue In-reply-to: <024601c71675$81277560$3cb16956@alex> References: <030b01c71651$984577c0$8300a8c0@tridecap.com> <01ea01c71653$438254e0$3cb16956@alex> <4571F856.7090808@enterprisedb.com> <022c01c7165f$17f49e80$3cb16956@alex> <4571FFA6.6070804@enterprisedb.com> <024601c71675$81277560$3cb16956@alex> Comments: In-reply-to "Alexandru Coseru" message dated "Sun, 03 Dec 2006 02:53:53 +0200" Date: Sat, 02 Dec 2006 23:05:12 -0500 Message-ID: <12526.1165118712@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200612/23 X-Sequence-Number: 22079 "Alexandru Coseru" writes: > Anyway , anybody has a clue why this regex is that CPU intensive ? The EXPLAIN result you posted offers *no* evidence that the regexp is CPU intensive. All you know is that it took 850+ msec to fetch 5200 rows from disk and apply the regexp filter to them. There's no evidence here that that was CPU time and not I/O time. regards, tom lane