From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx195.postini.com [74.125.245.195]) by kanga.kvack.org (Postfix) with SMTP id D81F16B005C for ; Wed, 30 May 2012 14:46:40 -0400 (EDT) Date: Wed, 30 May 2012 20:46:38 +0200 From: Andi Kleen Subject: Re: [PATCH 0/6] mempolicy memory corruption fixlet Message-ID: <20120530184638.GU27374@one.firstfloor.org> References: <1338368529-21784-1-git-send-email-kosaki.motohiro@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter Cc: Linus Torvalds , kosaki.motohiro@gmail.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Dave Jones , Mel Gorman , stable@vger.kernel.org, hughd@google.com, sivanich@sgi.com, KOSAKI Motohiro , andi@firstfloor.org On Wed, May 30, 2012 at 01:34:21PM -0500, Christoph Lameter wrote: > On Wed, 30 May 2012, Linus Torvalds wrote: > > > On Wed, May 30, 2012 at 2:02 AM, wrote: > > > > > > So, I think we should reconsider about shared mempolicy completely. > > > > Quite frankly, I'd prefer that approach. The code is subtle and > > horribly bug-fraught, and I absolutely detest the way it looks too. > > Reading your patches was actually somewhat painful. > > It is so bad mostly because the integration of shared memory policies with > cpusets is not really working. Using either in isolation is ok especially > shared mempolicies do not play well with cpusets. Yes the cpusets did some horrible things. I always regretted that cpusets were no done with custom node lists. That would have been much cleaner and also likely faster than what we have. > > If we could just remove the support for it entirely, that would be > > *much* preferable to continue working with this code. > > Well shm support needs memory policies to spread data across nodes etc. > AFAICT support was put in due to requirements to support large database > vendors (oracle). Andi? Yes we need shared policy for the big databases. Maybe we could stop supporting cpusets with that though. Not sure they really use that. > Its not going to be easy to remove. Shared policies? I don't think you can remove them. cpusets+shared policy? maybe, but still will be hard. -Andi > -- ak@linux.intel.com -- Speaking for myself only. -- 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 internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org