Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 1 Oct 2001 18:42:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 1 Oct 2001 18:42:19 -0400 Received: from e21.nc.us.ibm.com ([32.97.136.227]:250 "EHLO e21.nc.us.ibm.com") by vger.kernel.org with ESMTP id ; Mon, 1 Oct 2001 18:42:08 -0400 Importance: Normal Subject: Significant Performance Gain Due to Jonathan Lahr's io_request_lock Patch To: linux-kernel@vger.kernel.org, lse-tech@lists.sourceforge.net X-Mailer: Lotus Notes Release 5.0.8 June 18, 2001 Message-ID: From: "Peter Wong" Date: Mon, 1 Oct 2001 17:42:17 -0500 X-MIMETrack: Serialize by Router on D04NM203/04/M/IBM(Release 5.0.8 |June 18, 2001) at 10/01/2001 06:42:20 PM MIME-Version: 1.0 Content-type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org In August I reported that there was a 40% performance gain on a heavy database workload using Jens Axboe's zero-bounce highmem I/O patch and my IPS patch running 2.4.5 on a 4-way machine. This time I want to report the performance gain using the above two patches and Jonathan Lahr's io_request_lock patch running 2.4.6 on an 8-way machine. With Jens' patch and my patch, the total elapsed time for processing the queries was cut by 34%. With the above two patches as the baseline, Jonathan's io_request_lock patch cut the total elapsed time by an additional 36%. The CPU utilization corresponding to the bounce patches was 25% (user), 63% (kernel) and 12% (idle). With Jonathan's patch added, the CPU utilization became 40% (user), 29% (kernel) and 31% (idle). We can see that there was a significant drop in kernel time and an increase in idle time. In addition, I did not detect any system problems using Jonathan's patch during a lengthy period of heavy query processing. Jonathan's io_request_lock patch can be found at http://lse.sourceforge.net/io/. Regards, Peter Wai Yee Peter Wong IBM Linux Technology Center, Performance Analysis email: wpeter@us.ibm.com Office: (512) 838-9272, T/L 678-9272; Fax: (512) 838-4663 - 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/