Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263776AbUJ3AdN (ORCPT ); Fri, 29 Oct 2004 20:33:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263733AbUJ3A37 (ORCPT ); Fri, 29 Oct 2004 20:29:59 -0400 Received: from fw.osdl.org ([65.172.181.6]:9601 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S263749AbUJ3A0l (ORCPT ); Fri, 29 Oct 2004 20:26:41 -0400 Date: Fri, 29 Oct 2004 17:30:45 -0700 From: Andrew Morton To: Jesse Barnes Cc: linux-kernel@vger.kernel.org, jeremy@sgi.com Subject: Re: Buffered I/O slowness Message-Id: <20041029173045.32722ac0.akpm@osdl.org> In-Reply-To: <200410291716.25277.jbarnes@engr.sgi.com> References: <200410251814.23273.jbarnes@engr.sgi.com> <200410291046.48469.jbarnes@engr.sgi.com> <20041029160827.4dc29c3f.akpm@osdl.org> <200410291716.25277.jbarnes@engr.sgi.com> X-Mailer: Sylpheed version 0.9.7 (GTK+ 1.2.10; i586-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 X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 608 Lines: 14 Jesse Barnes wrote: > > > I'm not sure that we know what's going on yet. I certainly don't. The > > above numbers look good, so what's the problem??? > > The numbers are ~1/3 of what the machine is capable of with direct I/O. Are there CPU cycles to spare? If you have just one CPU copying 1GB/sec out of pagecache, maybe it is pegged? - 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/