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 C11C99DCC40 for ; Tue, 21 Mar 2006 06:08:53 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 20830-06 for ; Tue, 21 Mar 2006 06:08:55 -0400 (AST) 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 B1C399DCB0A for ; Tue, 21 Mar 2006 06:08:51 -0400 (AST) Received: by noel.decibel.org (Postfix, from userid 1001) id 26FDC56437; Tue, 21 Mar 2006 04:08:54 -0600 (CST) Received: (hashcash-sendmail, from uid 1001); Tue, 21 Mar 2006 04:08:53 -0600 Date: Tue, 21 Mar 2006 04:08:53 -0600 From: "Jim C. Nasby" To: Mark Kirkwood Cc: Scott Marlowe , Kenji Morishige , pgsql-performance@postgresql.org Subject: Re: Best OS & Configuration for Dual Xeon w/4GB & Message-ID: <20060321100852.GB15742@pervasive.com> References: <20060317221116.GA14661@juniper.net> <1142636433.1141.33.camel@state.g2switchworks.com> <20060320144503.GR15742@pervasive.com> <1142871620.17883.4.camel@state.g2switchworks.com> <441F6BA1.20005@paradise.net.nz> <441F7847.5000406@paradise.net.nz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <441F7847.5000406@paradise.net.nz> 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: 1:20:060321:markir@paradise.net.nz::hkRjnBV1KtdIsMbx:000000000000000 0000000000000000000000001OYe X-Hashcash: 1:20:060321:smarlowe@g2switchworks.com::xFKNAm2id7+y1AJo:00000000000 0000000000000000000000003PSC X-Hashcash: 1:20:060321:kenjim@juniper.net::wtWFjPFc2NIwlJho:0000000000000000000 0000000000000000000000004MDy X-Hashcash: 1:20:060321:pgsql-performance@postgresql.org::Swei1Teo8xuWxXx5:00000 00000000000000000000000047I/ X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.108 required=5 tests=[AWL=0.108] X-Spam-Score: 0.108 X-Spam-Level: X-Archive-Number: 200603/372 X-Sequence-Number: 17809 On Tue, Mar 21, 2006 at 03:51:35PM +1200, Mark Kirkwood wrote: > Mark Kirkwood wrote: > > > >I think Freebsd 'Inactive' corresponds pretty closely to Linux's > >'Inactive Dirty'|'Inactive Laundered'|'Inactive Free'. > > > > Hmmm - on second thoughts I think I've got that wrong :-(, since in > Linux all the file buffer pages appear in 'Cached' don't they... > > (I also notice that 'Inactive Laundered' does not seem to be mentioned > in vanilla - read non-Redhat - 2.6 kernels) > > So I think its more correct to say Freebsd 'Inactive' is similar to > Linux 'Inactive' + some|most of Linux 'Cached'. > > A good discussion of how the Freebsd vm works is here: > > http://www.freebsd.org/doc/en_US.ISO8859-1/books/arch-handbook/vm.html > > In particular: > > "FreeBSD reserves a limited amount of KVM to hold mappings from struct > bufs, but it should be made clear that this KVM is used solely to hold > mappings and does not limit the ability to cache data." It's worth noting that starting in either 2.4 or 2.6, linux pretty much adopted the FreeBSD VM system (or so I've been told). -- 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