From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964792AbWFHIE4 (ORCPT ); Thu, 8 Jun 2006 04:04:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964793AbWFHIE4 (ORCPT ); Thu, 8 Jun 2006 04:04:56 -0400 Received: from pne-smtpout1-sn2.hy.skanova.net ([81.228.8.83]:24813 "EHLO pne-smtpout1-sn2.hy.skanova.net") by vger.kernel.org with ESMTP id S964792AbWFHIEz (ORCPT ); Thu, 8 Jun 2006 04:04:55 -0400 Date: Thu, 8 Jun 2006 10:04:44 +0200 From: Voluspa To: Fengguang Wu Cc: Valdis.Kletnieks@vt.edu, diegocg@gmail.com, linux-kernel@vger.kernel.org Subject: Re: Adaptive Readahead V14 - statistics question... Message-Id: <20060608100444.5212162d.lista1@comhem.se> In-Reply-To: <349141076.14929@ustc.edu.cn> References: <20060530053631.57899084.lista1@comhem.se> <200605301649.k4UGnooZ004266@turing-police.cc.vt.edu> <20060531235021.41a58425.lista1@comhem.se> <349141076.14929@ustc.edu.cn> X-Mailer: Sylpheed version 1.0.4 (GTK+ 1.2.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org My patching was borked as can be seen in: http://marc.theaimsgroup.com/?l=linux-kernel&m=114956084026066&w=2 I've therefore benchmarked two corrected patches from Wu: http://web.comhem.se/~u46139355/storetmp/adaptive-readahead-2.6.17-rc5-wu-v1.patch http://web.comhem.se/~u46139355/storetmp/adaptive-readahead-2.6.17-rc5-wu-v2.patch Revised Conclusion: On _this_ machine, with _these_ operations, Adaptive Readahead in its current incarnation and default settings is a slight _loss_. However, if the readahead size is lowered from 2048 to 256, it becomes a slight _gain_ or at least stays in parity with normal readahead. I suggest others to test multi-thread, multi-cpu, more than/less than my 2GB memory, sata-disks, different disk speeds etc etc. Kernels: root:sleipner:~# ls -l /boot/kernel-2.6.17-rc5-git10* 1440 -rw-r--r-- 1 root root 1469326 Jun 6 22:27 /boot/kernel-2.6.17-rc5-git10 1440 -rw-r--r-- 1 root root 1470122 Jun 6 22:36 /boot/kernel-2.6.17-rc5-git10-ar1 1440 -rw-r--r-- 1 root root 1470128 Jun 6 22:44 /boot/kernel-2.6.17-rc5-git10-ar2 _Massive READ_ [/usr had some 195000 files] "cd /usr; time find . -type f -exec md5sum {} \; >/dev/null" [/sbin/blockdev --setra 256 /dev/hda] * [/sbin/blockdev --setra 2048 /dev/hda] 6.17-rc5-git10 - git10-ar1 - git10-ar2 * 6.17-rc5-git10 - git10-ar1 - git10-ar2 real 8m18.241s - 8m19.053s - 8m16.639s * real 8m24.042s - 8m22.652s - 8m20.812s user 1m23.556s - 1m24.526s - 1m23.725s * user 1m23.788s - 1m23.741s - 1m24.023s sys 2m8.514s - 2m5.989s - 2m3.540s * sys 2m7.369s - 2m6.914s - 2m5.317s real 8m19.171s - 8m17.993s - 8m17.062s * real 8m23.110s - 8m20.409s - 8m19.278s user 1m23.863s - 1m23.692s - 1m23.980s * user 1m23.770s - 1m23.715s - 1m23.525s sys 2m9.332s - 2m4.133s - 2m3.602s * sys 2m6.463s - 2m5.735s - 2m3.801s real 8m17.111s - 8m17.102s - 8m16.859s * real 8m21.891s - 8m19.129s - 8m17.321s user 1m24.071s - 1m24.126s - 1m24.430s * user 1m23.876s - 1m23.592s - 1m23.024s sys 2m6.292s - 2m3.543s - 2m3.142s * sys 2m4.768s - 2m4.012s - 2m3.110s real 8m20.427s - 8m16.972s - 8m17.847s * real 8m25.359s - 8m21.261s - 8m20.365s user 1m23.730s - 1m23.260s - 1m23.227s * user 1m24.242s - 1m23.825s - 1m23.895s sys 2m9.524s - 2m3.708s - 2m5.244s * sys 2m7.894s - 2m5.366s - 2m3.971s _READ/WRITE_ [255 .tga files, each is 1244178 bytes] [1 .wav file which is 1587644 bytes] [movie becomes 573298 bytes ~9s long] "time mencoder -ovc lavc -lavcopts aspect=16/9 mf://picsave/kreation/03-logo-joined/*.tga -oac lavc -audiofile kreation-files/kreation-logo-final.wav -o logo-final-widescreen-speedtest.avi" [/sbin/blockdev --setra 256 /dev/hda] * [/sbin/blockdev --setra 2048 /dev/hda] 6.17-rc5-git10 - git10-ar1 - git10-ar2 * 6.17-rc5-git10 - git10-ar1 - git10-ar2 real 0m12.961s - 0m12.864s - 0m12.811s * real 0m16.628s - 0m15.862s - 0m16.754s user 0m3.315s - 0m3.319s - 0m3.316s * user 0m3.335s - 0m3.301s - 0m3.308s sys 0m1.082s - 0m1.077s - 0m1.086s * sys 0m1.084s - 0m1.122s - 0m1.093s real 0m12.908s - 0m12.793s - 0m12.813s * real 0m16.601s - 0m15.893s - 0m16.736s user 0m3.323s - 0m3.305s - 0m3.312s * user 0m3.311s - 0m3.316s - 0m3.308s sys 0m1.051s - 0m1.079s - 0m1.145s * sys 0m1.046s - 0m1.109s - 0m1.091s _cp bigfile between different partitions_ [Elephants_Dream_HD.avi 854537054 bytes] "time cp /home/downloads/Elephants_Dream_HD.avi /root" [/sbin/blockdev --setra 256 /dev/hda] * [/sbin/blockdev --setra 2048 /dev/hda] 6.17-rc5-git10 - git10-ar1 - git10-ar2 * 6.17-rc5-git10 - git10-ar1 - git10-ar2 real 0m46.463s - 0m46.909s - 0m45.865s * real 0m50.232s - 0m50.863s - 0m50.549s user 0m0.081s - 0m0.073s - 0m0.068s * user 0m0.069s - 0m0.063s - 0m0.088s sys 0m6.304s - 0m7.204s - 0m5.949s * sys 0m5.902s - 0m7.174s - 0m6.822s real 0m46.126s - 0m47.305s - 0m47.174s * real 0m50.875s - 0m50.066s - 0m50.862s user 0m0.091s - 0m0.095s - 0m0.070s * user 0m0.099s - 0m0.091s - 0m0.071s sys 0m5.751s - 0m7.159s - 0m6.707s * sys 0m6.271s - 0m6.740s - 0m7.318s _cp filetree between different partitions_ [compiled kerneltree ~339M] "time cp -a /usr/src/testing/linux-2.6.17-rc5-git10 /root" [/sbin/blockdev --setra 256 /dev/hda] * [/sbin/blockdev --setra 2048 /dev/hda] 6.17-rc5-git10 - git10-ar1 - git10-ar2 * 6.17-rc5-git10 - git10-ar1 - git10-ar2 real 0m51.344s - 0m51.886s - 0m51.077s * real 0m52.502s - 0m52.757s - 0m54.794s user 0m0.193s - 0m0.220s - 0m0.231s * user 0m0.210s - 0m0.198s - 0m0.177s sys 0m5.508s - 0m6.003s - 0m5.205s * sys 0m5.980s - 0m5.800s - 0m6.372s real 0m51.148s - 0m51.212s - 0m51.768s * real 0m51.488s - 0m52.098s - 0m51.719s user 0m0.170s - 0m0.209s - 0m0.184s * user 0m0.198s - 0m0.210s - 0m0.179s sys 0m5.697s - 0m5.604s - 0m6.438s * sys 0m5.527s - 0m5.918s - 0m5.544s Mvh Mats Johannesson --