From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756597AbYIKXux (ORCPT ); Thu, 11 Sep 2008 19:50:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754990AbYIKXup (ORCPT ); Thu, 11 Sep 2008 19:50:45 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:49535 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754334AbYIKXuo (ORCPT ); Thu, 11 Sep 2008 19:50:44 -0400 Date: Thu, 11 Sep 2008 16:50:39 -0700 From: Andrew Morton To: Harun Scheutzow Cc: linux-kernel@vger.kernel.org Subject: Re: vfat file system extreme fragmentation on multiprocessor Message-Id: <20080911165039.d129a559.akpm@linux-foundation.org> In-Reply-To: <0ML29c-1KdqyO1YV1-0001g5@mrelayeu.kundenserver.de> References: <0ML29c-1KdqyO1YV1-0001g5@mrelayeu.kundenserver.de> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 11 Sep 2008 20:01:16 +0200 Harun Scheutzow wrote: > I like to share the following observation made with different kernels of 2.6.x series Yeah. ext2 and ext3 also showed major, major, major differences in layout quality (and hence performance) when switching between uniprocessor and multiprocessor environments, for the same reason. (UP was far better). It was fixed in ext3/4 by the in-core reservations code (recently ported into ext2 as well). This is why filesystem performance testing is far from complete if it is performed only on SMP (or UP) machines.