Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 27 Feb 2003 17:14:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 27 Feb 2003 17:14:56 -0500 Received: from 205-158-62-139.outblaze.com ([205.158.62.139]:9710 "HELO spf1.us.outblaze.com") by vger.kernel.org with SMTP id ; Thu, 27 Feb 2003 17:14:55 -0500 Message-ID: <20030227222440.14610.qmail@linuxmail.org> Content-Type: text/plain; charset="iso-8859-1" Content-Disposition: inline Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-Mailer: MIME-tools 5.41 (Entity 5.404) From: "Felipe Alfaro Solana" To: linux-kernel@vger.kernel.org Date: Thu, 27 Feb 2003 23:24:40 +0100 Subject: anticipatory scheduling questions X-Originating-Ip: 213.4.13.153 X-Originating-Server: ws5-2.us4.outblaze.com Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1552 Lines: 46 Hello, I have just installed 2.5.63-mm1 on my system and have been performing a very simple benchmarks. Here are my first results when compared against a RedHat 2.4.20-2.54 kernel: (All times expressed as total times) 1. time dd if=/dev/zero of=/tmp/p bs=1024k count=256 2.5.63-mm1 -> 0m12.737s 2.4.20-2.54 -> 0m17.704s 2. time cp /tmp/p /tmp/q 2.5.63-mm1 -> 0m41.108s 2.4.20-2.54 -> 0m51.939s 3. time cmp /tmp/p /tmp/q 2.5.63-mm1 -> 1m7.349s 2.4.20-2.54 -> 0m58.966s 4. time cmp /dev/zero /tmp/q 2.5.63-mm1 -> 0m17.965s 2.4.20-2.54 -> 0m14.038s The question is, why, apparently, is anticipatory scheduling perfomring worse than 2.4.20? Indeed, this can be tested interactively with an application like Evolution: I have configured Evolution to use 2 dictionaries (English and Spanish) for spell checking in e-mail messages. When running 2.4.20, if I choose to reply to a large message, it only takes a few seconds to read both dictionaries from disk and perform the spell checking. However, on 2.5.63-mm1 the same process takes considerably longer. Any reason for this? Thanks! Best regards, Felipe Alfaro Solana -- ______________________________________________ http://www.linuxmail.org/ Now with e-mail forwarding for only US$5.95/yr Powered by Outblaze - 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/