From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752095AbaB0UYn (ORCPT ); Thu, 27 Feb 2014 15:24:43 -0500 Received: from mx1.redhat.com ([209.132.183.28]:37750 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751550AbaB0UYm (ORCPT ); Thu, 27 Feb 2014 15:24:42 -0500 Message-ID: <530F9EB2.3070800@redhat.com> Date: Thu, 27 Feb 2014 15:23:14 -0500 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: Johannes Weiner , Mel Gorman CC: Andrew Morton , Jan Stancek , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [patch 1/2] mm: page_alloc: reset aging cycle with GFP_THISNODE References: <1393360022-22566-1-git-send-email-hannes@cmpxchg.org> <20140226095422.GY6732@suse.de> <20140226171206.GU6963@cmpxchg.org> <20140226201333.GV6963@cmpxchg.org> In-Reply-To: <20140226201333.GV6963@cmpxchg.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/26/2014 03:13 PM, Johannes Weiner wrote: > Would this be an acceptable replacement for 1/2? Looks reasonable to me. This should avoid the issues that were observed with NUMA migrations. > --- > > From: Johannes Weiner > Subject: [patch 1/2] mm: page_alloc: exempt GFP_THISNODE allocations from zone > fairness > > Jan Stancek reports manual page migration encountering allocation > failures after some pages when there is still plenty of memory free, > and bisected the problem down to 81c0a2bb515f ("mm: page_alloc: fair > zone allocator policy"). > > The problem is that GFP_THISNODE obeys the zone fairness allocation > batches on one hand, but doesn't reset them and wake kswapd on the > other hand. After a few of those allocations, the batches are > exhausted and the allocations fail. > > Fixing this means either having GFP_THISNODE wake up kswapd, or > GFP_THISNODE not participating in zone fairness at all. The latter > seems safer as an acute bugfix, we can clean up later. > > Reported-by: Jan Stancek > Signed-off-by: Johannes Weiner > Cc: # 3.12+ Acked-by: Rik van Riel