From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <48E4F6EC.7010500@linux-foundation.org> Date: Thu, 02 Oct 2008 11:29:32 -0500 From: Christoph Lameter MIME-Version: 1.0 Subject: Re: [PATCH 4/4] capture pages freed during direct reclaim for allocation by the reclaimer References: <1222864261-22570-1-git-send-email-apw@shadowen.org> <1222864261-22570-5-git-send-email-apw@shadowen.org> <48E390DA.9060109@linux-foundation.org> <20081002143508.GE11089@brain> In-Reply-To: <20081002143508.GE11089@brain> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andy Whitcroft Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, KOSAKI Motohiro , Peter Zijlstra , Rik van Riel , Mel Gorman , Nick Piggin , Andrew Morton List-ID: Andy Whitcroft wrote: >> At the beginning of reclaim just flush all pcp pages and then do not allow pcp >> refills again until reclaim is finished? > > Not entirely, some pages could get trapped there for sure. But it is > parallel allocations we are trying to guard against. Plus we already flush > the pcp during reclaim for higher orders. So we just would need to forbid refilling the pcp. Parallel allocations are less a problem if the freed order 0 pages get merged immediately into the order 1 freelist. Of course that will only work 50% of the time but it will have a similar effect to this patch. -- 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: email@kvack.org