From owner-freebsd-fs@FreeBSD.ORG Thu Jun 21 00:57:28 2007 Return-Path: X-Original-To: freebsd-fs@freebsd.org Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 69D4E16A468 for ; Thu, 21 Jun 2007 00:57:28 +0000 (UTC) (envelope-from tom.hurst@clara.net) Received: from spork.qfe3.net (spork.qfe3.net [212.13.207.101]) by mx1.freebsd.org (Postfix) with ESMTP id 2F36913C469 for ; Thu, 21 Jun 2007 00:57:27 +0000 (UTC) (envelope-from tom.hurst@clara.net) Received: from [81.104.144.87] (helo=voi.aagh.net) by spork.qfe3.net with esmtp (Exim 4.66 (FreeBSD)) (envelope-from ) id 1I1AeU-000Lgk-Gv; Thu, 21 Jun 2007 01:35:58 +0100 Received: from freaky by voi.aagh.net with local (Exim 4.67 (FreeBSD)) (envelope-from ) id 1I1AeU-000F4z-8R; Thu, 21 Jun 2007 01:35:58 +0100 Date: Thu, 21 Jun 2007 01:35:58 +0100 From: Thomas Hurst To: Vlad GURDIGA Message-ID: <20070621003558.GA55731@voi.aagh.net> Mail-Followup-To: Vlad GURDIGA , freebsd-fs@freebsd.org References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Not much. User-Agent: Mutt/1.5.15 (2007-04-06) Sender: Thomas Hurst Cc: freebsd-fs@freebsd.org Subject: Re: fs cache X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 21 Jun 2007 00:57:28 -0000 * Vlad GURDIGA (gurdiga@gmail.com) wrote: > The only difference I can see is that on Ubuntu, after first start of > Firefox the memory use for cache is 22% vs. 0% on FreeBSD. My guess is > that this is the cause of slower startups on FreeBSD. If you mean the "Cache" value in top, that's quite normal; "Cache" in FreeBSD doesn't mean quite the same as it does in Linux -- it's just one of several queues VM pages churn through depending on usage patterns and memory pressure. Most cached data will tend to reside in "Inact", where it's ready for quick use and modification, and it only cycles to "Cache" when the VM decides it's worth making clean (flushing to backing store if necessary) and marking read-only so it can be reused quickly (i.e. without touching a disk). And yes, Ubuntu doubtless does fancy prelinking/binding magic. This is a project idea listed on http://www.freebsd.org/projects/ideas/ and has had several attempts in the past from the look of it. -- Thomas 'Freaky' Hurst http://hur.st/