From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265395AbUFXPAF (ORCPT ); Thu, 24 Jun 2004 11:00:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265398AbUFXO76 (ORCPT ); Thu, 24 Jun 2004 10:59:58 -0400 Received: from [213.171.41.46] ([213.171.41.46]:53523 "EHLO kaamos.homelinux.net") by vger.kernel.org with ESMTP id S265395AbUFXO7Q (ORCPT ); Thu, 24 Jun 2004 10:59:16 -0400 From: Alexey Kopytov Organization: MySQL AB To: linux-kernel@vger.kernel.org Subject: Followup to random file I/O regressions Date: Thu, 24 Jun 2004 18:58:23 +0400 User-Agent: KMail/1.6.2 MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <200406241858.23356.alexeyk@mysql.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello! As a follow-up to my previous benchmark results posted a while back, I ran some more benchmarks on 2.4.27-rc1 and 2.6.7. Basically I was trying to spot a reason for remaining regressions. Summing up the results, 2.6.7 performs much better on this workload as compared to previous 2.6 kernels, but it seems like large file sizes and large numbers of files cause 2.6 to perform slower than 2.4 in the sysbench fileio tests. Test setup was an IDE hard drive with an ext3 partition with data=ordered, anticipatory scheduler for 2.6.7, LinuxThreads. The filesystem was remounted before each test run. All results below are average execution times of 3 sequential test runs with the same parameters. 16 threads, 128 files, variable total file size: 2.4.27-rc1 2.6.7 1 GB 73.78 75.75 2 GB 86.8 88.09 4 GB 99.02 108.99 8 GB 115.07 124.53 16 GB 134.69 136.63 It's interesting that 2.6 shows a significant regression on 4 and 8 GB, but only a minor regression on 16 GB. 1 thread, 4 GB total file size, variable number of files: 2.4.27-rc1 2.6.7 1 94 93.02 2 95.03 93.37 4 94.27 93.94 8 95.55 94.28 16 95.67 95.36 32 95.87 96.93 64 97.39 99.39 128 99.36 101.89 256 103.51 103.8 Here 2.6 shows better results for small number of files but worse for 32 and above files. 1 file, 4 GB total file size, variable number of threads: 2.4.27-rc1 2.6.7 1 94 93.02 2 96.6 93.26 4 94.93 90.16 8 89.49 87.45 16 86.25 86.2 32 88.14 85.13 Here 2.6 performs better in all tests. Formatted results and graphs are published on the sysbench homepage at http://sysbench.sourceforge.net/results/fileio/20040623.html Regards, Alexey. -- Alexey Kopytov, Software Developer MySQL AB, www.mysql.com Are you MySQL certified? www.mysql.com/certification