From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner+willy=40w.ods.org-S264918AbUEVId5@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S264918AbUEVId5 (ORCPT <rfc822;willy@w.ods.org>);
	Sat, 22 May 2004 04:33:57 -0400
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264915AbUEVId5
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Sat, 22 May 2004 04:33:57 -0400
Received: from fw.osdl.org ([65.172.181.6]:1774 "EHLO mail.osdl.org")
	by vger.kernel.org with ESMTP id S264917AbUEVId4 (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Sat, 22 May 2004 04:33:56 -0400
Date: Sat, 22 May 2004 01:33:13 -0700
From: Andrew Morton <akpm@osdl.org>
To: arjanv@redhat.com
Cc: axboe@suse.de, mason@suse.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ext3 barrier bits
Message-Id: <20040522013313.6cb15a4b.akpm@osdl.org>
In-Reply-To: <1085214261.2781.1.camel@laptop.fenrus.com>
References: <20040521093207.GA1952@suse.de>
	<20040521023807.0de63c7a.akpm@osdl.org>
	<20040521100234.GK1952@suse.de>
	<20040521235044.6160cccb.akpm@osdl.org>
	<20040522073540.GO1952@suse.de>
	<20040522011139.01a7da10.akpm@osdl.org>
	<1085214261.2781.1.camel@laptop.fenrus.com>
X-Mailer: Sylpheed version 0.9.7 (GTK+ 1.2.10; i386-redhat-linux-gnu)
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
X-Mailing-List: linux-kernel@vger.kernel.org

Arjan van de Ven <arjanv@redhat.com> wrote:
>
> 
> > - Does the kernel tell you if your disk doesn't supoprt barriers?  ie:
> >   how does the user know if it's working or not?
> 
> ... and how do you know your disk isn't lying and ignoring the barriers?
> 

If some benchmark slows down when barriers are enabled then that's a pretty
good indicator.  I don't know what benchmark that might be though.