Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S274888AbTGaW7T (ORCPT ); Thu, 31 Jul 2003 18:59:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S274898AbTGaW7S (ORCPT ); Thu, 31 Jul 2003 18:59:18 -0400 Received: from dyn-ctb-210-9-244-141.webone.com.au ([210.9.244.141]:11524 "EHLO chimp.local.net") by vger.kernel.org with ESMTP id S274888AbTGaW5u (ORCPT ); Thu, 31 Jul 2003 18:57:50 -0400 Message-ID: <3F299EA2.9020409@cyberone.com.au> Date: Fri, 01 Aug 2003 08:56:34 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.3.1) Gecko/20030618 Debian/1.3.1-3 X-Accept-Language: en MIME-Version: 1.0 To: Oliver Neukum CC: Jamie Lokier , Con Kolivas , Andrew Morton , Johoho , wodecki@gmx.de, Valdis.Kletnieks@vt.edu, linux-kernel@vger.kernel.org Subject: Re: [PATCH] O10int for interactivity References: <200307280112.16043.kernel@kolivas.org> <200307311743.17370.kernel@kolivas.org> <20030731145937.GD6410@mail.jlokier.co.uk> <200307311724.12738.oliver@neukum.org> In-Reply-To: <200307311724.12738.oliver@neukum.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1614 Lines: 44 Oliver Neukum wrote: >>>This part interests me. It would seem that either >>>1. The AS scheduler should not bother waiting at all if the process is not >>>going to wake up in that time >>> >>How about something as simple as: if process sleeps, and AS scheduler >>is waiting since last request from that process, AS scheduler stops >>waiting immediately? >> No its fine if the process were to sleep on something. Its the amount of time between IOs that is important (and is measured). Makes no difference if the process is computing something or waiting for something really. >> >>In other words, a hook in the process scheduler when a process goes to >>sleep, to tell the AS scheduler to stop waiting. >> >>Although this would not always be optimal, for many cases the point of >>AS is that the process is continuing to run, not sleeping, and will >>issue another request shortly. >> > >How do you tell which task dirtied the page? >Wouldn't giving a bonus to tasks doing file io achieve the same purpose? >Also, isn't quickly waking up tasks more important? > With AS, it doesn't matter what task created the IO, its what task will have to wait on it. In the case of async writes, we don't care about them anyway because the pagecache means they get done a long way behind the instruction pointer of the process anyway, so they'll be nicely layed out anyway. - 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/