From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 21 Sep 2001 08:29:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 21 Sep 2001 08:29:19 -0400 Received: from hal.grips.com ([62.144.214.40]:2458 "EHLO hal.grips.com") by vger.kernel.org with ESMTP id ; Fri, 21 Sep 2001 08:29:03 -0400 Message-Id: <200109211229.f8LCT9J19687@hal.grips.com> Content-Type: text/plain; charset=US-ASCII From: Gerold Jury To: Robert Love Subject: Re: Feedback on preemptible kernel patch xfs Date: Fri, 21 Sep 2001 14:29:08 +0200 X-Mailer: KMail [version 1.3.1] In-Reply-To: <1000581501.32705.46.camel@phantasy> <3BA94B2E.99FABD43@grips.com> <1000947409.4348.58.camel@phantasy> In-Reply-To: <1000947409.4348.58.camel@phantasy> Cc: linux-kernel@vger.kernel.org MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 20 September 2001 02:56, Robert Love wrote: > I am surprised, you should see a difference, especially with the > latencytest. Silly question, but you both applied the patch and enabled > the config statement, right? > Really, i have checked twice. The patch could, by the way, write a line to the syslog when enabled. All the filesystem operations happend on the xfs partitions. I noticed more equally distributed read/write operations with smaller slices during big copy jobs on xfs. This effect may well come from the preemption patch. I used a spare partition for the test, so the filesystem was in the same state with both kernels during the tests. Xfs usually delays the write operations and does them in bigger blocks. The behavior of XFS has changed with the kernel versions towards this direction anyway but is clearly different with the preemption patch. I will redo the latency tests with the standard Xfree86 nvidia driver. It may give a different picture. The graphics test and the /proc test have shown the highest latency's. Both involve the xserver (proc for the xterm). The other tests have been around 5-6 msec in both cases. And i will do the dbench test of course. Gerold