Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262296AbTHTWqn (ORCPT ); Wed, 20 Aug 2003 18:46:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262315AbTHTWqm (ORCPT ); Wed, 20 Aug 2003 18:46:42 -0400 Received: from mail.jlokier.co.uk ([81.29.64.88]:33154 "EHLO mail.jlokier.co.uk") by vger.kernel.org with ESMTP id S262304AbTHTWql (ORCPT ); Wed, 20 Aug 2003 18:46:41 -0400 Date: Wed, 20 Aug 2003 23:46:28 +0100 From: Jamie Lokier To: Denis Vlasenko Cc: Sergey Spiridonov , linux-kernel@vger.kernel.org Subject: Re: how to turn off, or to clear read cache? Message-ID: <20030820224628.GA24639@mail.jlokier.co.uk> References: <3F4360F0.209@gamic.com> <200308201311.h7KDBgL20530@Port.imtp.ilyichevsk.odessa.ua> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200308201311.h7KDBgL20530@Port.imtp.ilyichevsk.odessa.ua> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 928 Lines: 23 Denis Vlasenko wrote: > On 20 August 2003 14:52, Sergey Spiridonov wrote: > > I need to make some performance tests. I need to switch off or to clear > > read cache, so that consequent reading of the same file will take the > > same amount of time. > > umount/mount cycle will do it, as well as intentional OOMing the box > (from non-root account please;) umount/mount is impractical when you're testing performance on a big filesystem, which is always being used (e.g. /home). I'm fairly sure that -o remount used to have this side effect, in fact I used it quite a lot for that purpose, so it should be possible to make it work again, or add a -o flushcache option. -- Jamie - 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/