From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752039AbcDZON7 (ORCPT ); Tue, 26 Apr 2016 10:13:59 -0400 Received: from mx2.suse.de ([195.135.220.15]:43879 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751735AbcDZON6 (ORCPT ); Tue, 26 Apr 2016 10:13:58 -0400 Subject: Re: [PATCH 16/28] mm, page_alloc: Move __GFP_HARDWALL modifications out of the fastpath To: Mel Gorman , Andrew Morton References: <1460710760-32601-1-git-send-email-mgorman@techsingularity.net> <1460711275-1130-1-git-send-email-mgorman@techsingularity.net> <1460711275-1130-4-git-send-email-mgorman@techsingularity.net> Cc: Jesper Dangaard Brouer , Linux-MM , LKML From: Vlastimil Babka Message-ID: <571F77A0.2010207@suse.cz> Date: Tue, 26 Apr 2016 16:13:52 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.7.1 MIME-Version: 1.0 In-Reply-To: <1460711275-1130-4-git-send-email-mgorman@techsingularity.net> Content-Type: text/plain; charset=iso-8859-2; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/15/2016 11:07 AM, Mel Gorman wrote: > __GFP_HARDWALL only has meaning in the context of cpusets but the fast path > always applies the flag on the first attempt. Move the manipulations into > the cpuset paths where they will be masked by a static branch in the common > case. > > With the other micro-optimisations in this series combined, the impact on > a page allocator microbenchmark is > > 4.6.0-rc2 4.6.0-rc2 > decstat-v1r20 micro-v1r20 > Min alloc-odr0-1 381.00 ( 0.00%) 377.00 ( 1.05%) > Min alloc-odr0-2 275.00 ( 0.00%) 273.00 ( 0.73%) > Min alloc-odr0-4 229.00 ( 0.00%) 226.00 ( 1.31%) > Min alloc-odr0-8 199.00 ( 0.00%) 196.00 ( 1.51%) > Min alloc-odr0-16 186.00 ( 0.00%) 183.00 ( 1.61%) > Min alloc-odr0-32 179.00 ( 0.00%) 175.00 ( 2.23%) > Min alloc-odr0-64 174.00 ( 0.00%) 172.00 ( 1.15%) > Min alloc-odr0-128 172.00 ( 0.00%) 170.00 ( 1.16%) > Min alloc-odr0-256 181.00 ( 0.00%) 183.00 ( -1.10%) > Min alloc-odr0-512 193.00 ( 0.00%) 191.00 ( 1.04%) > Min alloc-odr0-1024 201.00 ( 0.00%) 199.00 ( 1.00%) > Min alloc-odr0-2048 206.00 ( 0.00%) 204.00 ( 0.97%) > Min alloc-odr0-4096 212.00 ( 0.00%) 210.00 ( 0.94%) > Min alloc-odr0-8192 215.00 ( 0.00%) 213.00 ( 0.93%) > Min alloc-odr0-16384 216.00 ( 0.00%) 214.00 ( 0.93%) > > Signed-off-by: Mel Gorman Acked-by: Vlastimil Babka