From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 2 Feb 2005 14:49:36 -0200 From: Marcelo Tosatti Subject: Re: [PATCH 2/2] Helping prezoring with reduced fragmentation allocation Message-ID: <20050202164936.GA23718@logos.cnet> References: <20050201171641.CC15EE5E8@skynet.csn.ul.ie> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org Return-Path: To: akpm@osdl.org Cc: Christoph Lameter , Mel Gorman , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: Hi Andrew, What are your thoughts about inclusion of Mel's allocator work on -mm ? On Wed, Feb 02, 2005 at 12:31:36AM +0000, Mel Gorman wrote: > On Tue, 1 Feb 2005, Christoph Lameter wrote: > > > On Tue, 1 Feb 2005, Mel Gorman wrote: > > > > > > Would it not be better to zero the global 2^MAX_ORDER pages by the scrub > > > > daemon and have a global zeroed page list? That way you may avoid zeroing > > > > when splitting pages? > > > > > > > > > > Maybe, but right now when there are no 2^MAX_ORDER pages, the scrub daemon > > > is going to be doing nothing which is why I think it needs to look at the > > > free pages of lower orders. > > > > > > That is solveable though in one of two ways. One, the scrub daemon can > > > zero pages from the global list and then add them to the USERZERO pool. It > > > has the advantage of requiring no more memory and is simple. The second is > > > to create a second global list. However, I think it only makes sense to > > > have this as part of the scrub daemon patch (I can write it if thats a > > > problem) rather than a standalone patch from me. > > > > Approach one is fine and I will do an update the remaining prezero patches > > to do just that. > > There is another problem with approach one. Assuming all 2^MAX_ORDER pages > have been zeroed and in USERZERO pool and there are no other free pages, > an allocation for the USERRCLM pool would search all the other pools > before finding the zerod pages. This could really slow things up but it is > not a problem approach two suffers from. > > > When will your patches be in Linus tree? ;-) > > > > Your guess is as good as mine :) . I am fairly sure the allocator is > somewhere in Andrew's list of patches to look at to consider for inclusion > into -mm so I suppose it'll get a spin in that tree when he feels it's > ready. -- 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/ . Don't email: aart@kvack.org