From owner-freebsd-geom@FreeBSD.ORG Wed Jul 5 20:41:28 2006 Return-Path: X-Original-To: freebsd-geom@freebsd.org Delivered-To: freebsd-geom@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id ED91D16A4DE for ; Wed, 5 Jul 2006 20:41:28 +0000 (UTC) (envelope-from anderson@centtech.com) Received: from mh1.centtech.com (moat3.centtech.com [207.200.51.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id 15CD643D53 for ; Wed, 5 Jul 2006 20:41:27 +0000 (GMT) (envelope-from anderson@centtech.com) Received: from [10.177.171.220] (neutrino.centtech.com [10.177.171.220]) by mh1.centtech.com (8.13.1/8.13.1) with ESMTP id k65KfQWd039956; Wed, 5 Jul 2006 15:41:26 -0500 (CDT) (envelope-from anderson@centtech.com) Message-ID: <44AC23FA.8040606@centtech.com> Date: Wed, 05 Jul 2006 15:41:30 -0500 From: Eric Anderson User-Agent: Thunderbird 1.5.0.4 (X11/20060612) MIME-Version: 1.0 To: "R. B. Riddick" References: <20060705190511.67863.qmail@web30307.mail.mud.yahoo.com> In-Reply-To: <20060705190511.67863.qmail@web30307.mail.mud.yahoo.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: ClamAV 0.87.1/1586/Wed Jul 5 14:22:07 2006 on mh1.centtech.com X-Virus-Status: Clean Cc: freebsd-geom@freebsd.org Subject: Re: new class / geom_cache / request for comments X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 05 Jul 2006 20:41:29 -0000 R. B. Riddick wrote: > --- Eric Anderson wrote: >> Just curious, how is this different/better than the regular buffer cache? >> > Hi Eric! > > The buffer cache? :-) > [This remembers me on the episode in The Simpsons where Mr.Burns tried to find > the meaning of "re-cyc-ling" in his builtin dictionary] > > Do you mean this cache of those file systems? > If yes: The answer should be: "It just makes everything worse." (there is not > even some read ahead...) Not sure what I'm missing here, please clue me in. I guess I am indeed talking about the cache normally used for filesystems. If I read a 500MB file in, first time it comes from disk, second time it comes from memory cache, correct? How is geom_cache different? > It is just useful, if you dont have any other caches (e. g. a ufs on a > geom_raid5 (I think I should have it tomorrow... :-) ) on some geom_cache > providers)... I suppose I just need to play with it to completely understand.. Eric -- ------------------------------------------------------------------------ Eric Anderson Sr. Systems Administrator Centaur Technology Anything that works is better than anything that doesn't. ------------------------------------------------------------------------