From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with SMTP id 3DD188D0030 for ; Mon, 1 Nov 2010 02:26:20 -0400 (EDT) Date: Mon, 1 Nov 2010 17:24:46 +1100 From: Dave Chinner Subject: Re: [PATCH 00/17] [RFC] soft and dynamic dirty throttling limits Message-ID: <20101101062446.GK2715@dastard> References: <20100912154945.758129106@intel.com> <20101012141716.GA26702@infradead.org> <20101013030733.GV4681@dastard> <20101013082611.GA6733@localhost> <20101013092627.GY4681@dastard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101013092627.GY4681@dastard> Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Christoph Hellwig , linux-mm , LKML , Andrew Morton , Theodore Ts'o , Jan Kara , Peter Zijlstra , Mel Gorman , Rik van Riel , KOSAKI Motohiro , Chris Mason , Christoph Hellwig , "Li, Shaohua" List-ID: On Wed, Oct 13, 2010 at 08:26:27PM +1100, Dave Chinner wrote: > On Wed, Oct 13, 2010 at 04:26:12PM +0800, Wu Fengguang wrote: > > On Wed, Oct 13, 2010 at 11:07:33AM +0800, Dave Chinner wrote: > > > On Tue, Oct 12, 2010 at 10:17:16AM -0400, Christoph Hellwig wrote: > > > > Wu, what's the state of this series? It looks like we'll need it > > > > rather sooner than later - try to get at least the preparations in > > > > ASAP would be really helpful. > > > > > > Not ready in it's current form. This load (creating millions of 1 > > > byte files in parallel): > > > > > > $ /usr/bin/time ./fs_mark -D 10000 -S0 -n 100000 -s 1 -L 63 \ > > > > -d /mnt/scratch/0 -d /mnt/scratch/1 \ > > > > -d /mnt/scratch/2 -d /mnt/scratch/3 \ > > > > -d /mnt/scratch/4 -d /mnt/scratch/5 \ > > > > -d /mnt/scratch/6 -d /mnt/scratch/7 > > > > > > Locks up all the fs_mark processes spinning in traces like the > > > following and no further progress is made when the inode cache > > > fills memory. > > > > I reproduced the problem on a 6G/8p 2-socket 11-disk box. > > > > The root cause is, pageout() is somehow called with low scan priority, > > which deserves more investigation. > > > > The direct cause is, balance_dirty_pages() then keeps nr_dirty too low, > > which can be improved easily by not pushing down the soft dirty limit > > to less than 1-second worth of dirty pages. > > > > My test box has two nodes, and their memory usage are rather unbalanced: > > (Dave, maybe you have NUMA setup too?) > > No, I'm running the test in a single node VM. > > FYI, I'm running the test on XFS (16TB 12 disk RAID0 stripe), using > the mount options "inode64,nobarrier,logbsize=262144,delaylog". Any update on the current status of this patchset? Cheers, Dave. -- Dave Chinner david@fromorbit.com -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org