X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.2]) by svr1.postgresql.org (Postfix) with ESMTP id 03DBAD1B547 for ; Tue, 14 Oct 2003 00:12:34 +0000 (GMT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (neptune.hub.org [200.46.204.2]) (amavisd-new, port 10024) with ESMTP id 72095-02 for ; Mon, 13 Oct 2003 21:12:03 -0300 (ADT) Received: from sss.pgh.pa.us (unknown [192.204.191.242]) by svr1.postgresql.org (Postfix) with ESMTP id 04149D1B538 for ; Mon, 13 Oct 2003 21:12:02 -0300 (ADT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.12.10/8.12.10) with ESMTP id h9E0Bthn003817; Mon, 13 Oct 2003 20:11:55 -0400 (EDT) To: Sean Chittenden Cc: Josh Berkus , Christopher Kings-Lynne , Nick Barr , pgsql-performance@postgresql.org Subject: Re: go for a script! / ex: PostgreSQL vs. MySQL In-reply-to: <20031013191023.GB72842@perrin.nxad.com> References: <007901c38f2b$0b585590$2802a8c0@webbased10> <3F8819EF.7010004@chuckie.co.uk> <3F88BFD7.1020808@familyhealth.com.au> <200310121331.42693.josh@agliodbs.com> <20031013191023.GB72842@perrin.nxad.com> Comments: In-reply-to Sean Chittenden message dated "Mon, 13 Oct 2003 12:10:23 -0700" Date: Mon, 13 Oct 2003 20:11:55 -0400 Message-ID: <3816.1066090315@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: by amavisd-new at postgresql.org X-Archive-Number: 200310/440 X-Sequence-Number: 4188 Sean Chittenden writes: > Every few months one of the uber core BSD hackers threatens to rewrite > that part of PG because high up in the BSD camp, it's common belief > that shm* is a source of performance loss for PostgreSQL. They're full of it. RAM is RAM, no? Once you've got the memory mapped into your address space, it's hard to believe that it matters how you got hold of it. In any case, mmap doesn't have the semantics we need. See past discussions. regards, tom lane