From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932511AbVHaMYK (ORCPT ); Wed, 31 Aug 2005 08:24:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932514AbVHaMYK (ORCPT ); Wed, 31 Aug 2005 08:24:10 -0400 Received: from smtp203.mail.sc5.yahoo.com ([216.136.129.93]:15247 "HELO smtp203.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S932511AbVHaMYI (ORCPT ); Wed, 31 Aug 2005 08:24:08 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=zd+uoFbGj2xkJeVYVgV4KNpO4tYWJkxRO3qK7GPkhs28hu8SpFUEUQX8FK/w5UyFzEnT+tZpJ5tzDgEEONxZIYY7ghsOVRWFx/JVDnQwzjBdA2nRBZjK5rQvkv22Ye/8PYsxRhTALWcVzhhtmi1n9vpiErcLiubL7Fgxc1MhbcM= ; Message-ID: <4315A179.8070102@yahoo.com.au> Date: Wed, 31 Aug 2005 22:24:25 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.10) Gecko/20050802 Debian/1.7.10-1 X-Accept-Language: en MIME-Version: 1.0 To: Holger Kiehl CC: Jens Axboe , Vojtech Pavlik , linux-raid , linux-kernel Subject: Re: Where is the performance bottleneck? References: <20050829202529.GA32214@midnight.suse.cz> <20050831071126.GA7502@midnight.ucw.cz> <20050831072644.GF4018@suse.de> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Holger Kiehl wrote: > 3236497 total 1.4547 > 2507913 default_idle 52248.1875 > 158752 shrink_zone 43.3275 > 121584 copy_user_generic_c 3199.5789 > 34271 __wake_up_bit 713.9792 > 31131 __make_request 23.1629 > 22096 scsi_request_fn 18.4133 > 21915 rotate_reclaimable_page 80.5699 ^^^^^^^^^ I don't think this function should be here. This indicates that lots of writeout is happening due to pages falling off the end of the LRU. There was a bug recently causing memory estimates to be wrong on Opterons that could cause this I think. Can you send in 2 dumps of /proc/vmstat taken 10 seconds apart while you're writing at full speed (with 2.6.13 or the latest -git tree). A dump of /proc/zoneinfo and /proc/meminfo while the write is going on would be helpful too. Thanks, Nick -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com