Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 5 Apr 2002 13:43:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 5 Apr 2002 13:43:44 -0500 Received: from ip68-7-112-74.sd.sd.cox.net ([68.7.112.74]:61710 "EHLO clpanic.kennet.coplanar.net") by vger.kernel.org with ESMTP id ; Fri, 5 Apr 2002 13:43:38 -0500 Message-ID: <007901c1dcd1$c446bb90$7e0aa8c0@bridge> From: "Jeremy Jackson" To: "dean gaudet" , "Andrew Morton" Cc: , In-Reply-To: Subject: Re: faster boots? Date: Fri, 5 Apr 2002 10:43:21 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4807.1700 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4807.1700 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org It may be interesting to note that SGI's XFS has a "realtime section" or some such, which has no metadata, only data blocks. Perhaps DMAPI has methods for moving files around on a live fs. If you know what you want in there. Jeremy ----- Original Message ----- From: "dean gaudet" To: "Andrew Morton" Cc: ; Sent: Thursday, April 04, 2002 11:45 PM Subject: Re: faster boots? > On Thu, 4 Apr 2002, Andrew Morton wrote: > > > I guess the greatest benefit would come from reorganising the > > layout of the root filesystem's data and metadata so the > > pagecache prepopulation doesn't have to seek all over the place. > > windows xp does this automatically (but it takes a lot of idle time before > it'll start playing with your disk)... search for "bootvis" at > microsoft.com, that tool can force the reorganization to occur. it's > worth 10%ish there as well (quite noticeable on laptops). they appear to > reorganize the boot-time files into one big contiguous region. that's > fetched into their equivalent of the page cache with sequential reads. > > it's certainly interesting theory -- trying to do disk layout which is > optimised for particular access patterns... it's kind of a hack to do this > just for boot time, but definitely educational :) > > in some ways, the filesystem is the wrong place to do this type of > activity -- you could approach the problem as a block layer device between > the fs and the hardware which maintains statistics on access patterns and > moves blocks around to optimise access time -- which lets you fix all > sorts of seeking problems. i guess the challenge would be maintaining a > map of logical block number to physical block number. hmm. guess that's > kind of hard. > > -dean > > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/