From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759230AbYESXGL (ORCPT ); Mon, 19 May 2008 19:06:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754833AbYESXF5 (ORCPT ); Mon, 19 May 2008 19:05:57 -0400 Received: from BISCAYNE-ONE-STATION.MIT.EDU ([18.7.7.80]:38092 "EHLO biscayne-one-station.mit.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756042AbYESXF5 (ORCPT ); Mon, 19 May 2008 19:05:57 -0400 Date: Mon, 19 May 2008 19:05:11 -0400 From: Theodore Tso To: Dave Young Cc: kernel list , Andrew Morton Subject: Re: [2.6.26-rc2-mm1] sync to speed up? Message-ID: <20080519230511.GL15035@mit.edu> Mail-Followup-To: Theodore Tso , Dave Young , kernel list , Andrew Morton References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.15+20070412 (2007-04-11) X-Spam-Flag: NO X-Spam-Score: 0.00 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 19, 2008 at 03:15:09PM +0800, Dave Young wrote: > Hi, > > With 2.6.26-rc2-mm1 I need to sync frequently. It's not normal as my > understanding. > > 1. scp a big file from a lan server. Firstly the speed is about 8M/s, > but the speed will slow down to 100K/s at last. After I exec "sync", > the speed will restore. > > Is this a known issue? Dave, what filesystem are you using? Jiri's patch on this thread was to fix a problem in ext4, which means that's fixing a problem which is unrelated to the slow mkfs.ext2 problem (which is writing to a block device, not a file in a ext4 filesystem), and so it's likely unrelated to your problem (unless you're using ext4 and didn't tell us :-). Andrew's probably right that it may be related to the slow mkfs problem. Can you confirm that you are seeing this on 2.6.26-rc2-mm1, but not on stock 2.6.26.rc2? - Ted