Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266081AbUFJBDL (ORCPT ); Wed, 9 Jun 2004 21:03:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266085AbUFJBDK (ORCPT ); Wed, 9 Jun 2004 21:03:10 -0400 Received: from sb0-cf9a48a7.dsl.impulse.net ([207.154.72.167]:63203 "EHLO madrabbit.org") by vger.kernel.org with ESMTP id S266081AbUFJBDG (ORCPT ); Wed, 9 Jun 2004 21:03:06 -0400 Subject: Re: 2.6 vm/elevator loading down disks where 2.4 does not From: Ray Lee To: Clint Byrum Cc: Linux Kernel In-Reply-To: <2c0942db04060917542cb15077@mail.gmail.com> References: <1086724300.5467.161.camel@localhost> <2c0942db04060917542cb15077@mail.gmail.com> Content-Type: text/plain Organization: http://madrabbit.org/ Message-Id: <1086829384.13085.10.camel@orca.madrabbit.org> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Wed, 09 Jun 2004 18:03:05 -0700 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 894 Lines: 25 > Upon investigation, we saw that the 2.6 box was reading from the disk > about 5 times as much as 2.4. I don't think this will account for the entire change in disk activity, but 2.6.7-pre? contains a fix for the read ahead code to prevent it from reading extra sectors when unneeded. The fix applies to 'seeky database type loads' which... > The data access patterns are generally "search through index files in > a tree-walking type of manner, then seek to data records in data > files." ...sounds like it may apply to you. So, if you and your server have some time, you might try 2.6.7rc3 and see if it changes any of the numbers. Ray Lee - 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/