Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 6 Dec 2001 06:31:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 6 Dec 2001 06:31:24 -0500 Received: from mustard.heime.net ([194.234.65.222]:51398 "EHLO mustard.heime.net") by vger.kernel.org with ESMTP id ; Thu, 6 Dec 2001 06:31:21 -0500 Date: Thu, 6 Dec 2001 12:31:03 +0100 (CET) From: Roy Sigurd Karlsbakk To: Andrew Morton cc: Subject: Re: /proc/sys/vm/(max|min)-readahead effect???? In-Reply-To: <3C0E7FEE.2770EDF4@zip.com.au> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Thanks! It works On Wed, 5 Dec 2001, Andrew Morton wrote: > Roy Sigurd Karlsbakk wrote: > > > > hi all > > > > I've just upgraded to 2.4.16 to get /proc/sys/vm/(max|min)-readahead > > available. I've got this idea... > > > > If lots of files (some hundered) are read simultaously, I waste all the > > i/o time in seeks. However, if I increase the readahead, it'll read more > > data at a time, and end up with seeking a lot less. > > > > The harddrive I'm testing this with, is a cheap 20G IDE drive. > > /proc/sys/vm/*-readhead is a no-op for IDE. It doesn't do > anything. You must use > > echo file_readahead:100 > /proc/ide/ide0/hda/settings > > to set the readhead to 100 pages (409600 bytes). > > - > -- Roy Sigurd Karlsbakk, MCSE, MCNE, CLS, LCA Computers are like air conditioners. They stop working when you open Windows. - 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/