From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id 26F466B0098 for ; Wed, 15 Dec 2010 21:14:57 -0500 (EST) Date: Thu, 16 Dec 2010 03:13:53 +0100 From: Andrea Arcangeli Subject: Re: Transparent Hugepage Support #33 Message-ID: <20101216021353.GD5638@random.random> References: <20101215051540.GP5638@random.random> <20101216095408.3a60cbad.kamezawa.hiroyu@jp.fujitsu.com> <20101216101053.05cb1516.nishimura@mxp.nes.nec.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101216101053.05cb1516.nishimura@mxp.nes.nec.co.jp> Sender: owner-linux-mm@kvack.org To: Daisuke Nishimura Cc: KAMEZAWA Hiroyuki , linux-mm@kvack.org, Linus Torvalds , Andrew Morton , linux-kernel@vger.kernel.org, Marcelo Tosatti , Adam Litke , Avi Kivity , Hugh Dickins , Rik van Riel , Mel Gorman , Dave Hansen , Benjamin Herrenschmidt , Ingo Molnar , Mike Travis , Christoph Lameter , Chris Wright , bpicco@redhat.com, KOSAKI Motohiro , Balbir Singh , "Michael S. Tsirkin" , Peter Zijlstra , Johannes Weiner , Chris Mason , Borislav Petkov , Miklos Szeredi List-ID: Hi Daisuke and Kame, On Thu, Dec 16, 2010 at 10:10:53AM +0900, Daisuke Nishimura wrote: > Hi, > > On Thu, 16 Dec 2010 09:54:08 +0900 > KAMEZAWA Hiroyuki wrote: > > > On Wed, 15 Dec 2010 06:15:40 +0100 > > Andrea Arcangeli wrote: > > > > > Some of some relevant user of the project: > > > > > > KVM Virtualization > > > GCC (kernel build included, requires a few liner patch to enable) > > > JVM > > > VMware Workstation > > > HPC > > > > > > It would be great if it could go in -mm. > > > > Things should be done in memory cgroup is > > > > - make accounting correct (RSS count will be broken) > > - make move_charge() to work > > (at rmdir(), this is now broken. It seems move-charge-at-task-move to work) > > > Yes. > I think we should add mem_cgroup_split_hugepage_commit() and add PageTransHuge() > check in mem_cgroup_move_parent() as done in RHEL6 kernel. Yes, unfortunately porting all the RHEL6 THP cgroups bits wasn't trivial because of the difference in the cgroup code. > As for move-charge-at-task-move, it will work because walk_pmd_range() splits > THP pages(it would be better to change move-charge not to split THP pages, but > it's not so urgent IMHO). > > > Do you have known other viewpoints ? > Not yet, but I'll test and check. Same here. One detail I'd ask you to check is the compound_trans_order I added in #33 for memory-failure and cgroups. It's not really necessary in memcg if we stop reading the order and we do page_size = HPAGE_PMD_SIZE instead. I thought having the cgroup code handling compound pages without hardwiring the size was better but maybe it's not. Maybe the compound_lock locking should also be extended there? It's up to you to what you prefer there but I'll try to help as much as I can. BTW, now that it's in -mm I'll keep any further change incremental at the end and I'll stop rebasing to avoid confusion. > > I'll look into when -mm is shipped. > > > me too :) Thanks a lot! -- 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