Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 23 Feb 2003 10:23:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 23 Feb 2003 10:23:16 -0500 Received: from [195.223.140.107] ([195.223.140.107]:20870 "EHLO athlon.random") by vger.kernel.org with ESMTP id ; Sun, 23 Feb 2003 10:23:15 -0500 Date: Sun, 23 Feb 2003 16:34:39 +0100 From: Andrea Arcangeli To: Andrew Morton Cc: Andi Kleen , linux-kernel@vger.kernel.org Subject: Re: [ak@suse.de: Re: iosched: impact of streaming read on read-many-files] Message-ID: <20030223153439.GE29467@dualathlon.random> References: <20030222054307.GA22074@wotan.suse.de> <20030221230716.630934cf.akpm@digeo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030221230716.630934cf.akpm@digeo.com> User-Agent: Mutt/1.4i X-GPG-Key: 1024D/68B9CB43 X-PGP-Key: 1024R/CB4660B9 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 842 Lines: 17 On Fri, Feb 21, 2003 at 11:07:16PM -0800, Andrew Morton wrote: > request within ten milliseconds is an impossibility. Attempting to > achieve it will result in something which seeks all over the place. This is called SFQ, or CFQ with 0 dispatch queue level and it works fine (given a fixed amount of tasks doing I/O). You still don't understand you don't care about throughput and seeks if you only need to read 1 block with the max fairness and you don't mind to read another block within 1 second. seeking is the last problem here, waiting more than 1 second is the only problem here. Andrea - 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/