From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758292AbZBVXWY (ORCPT ); Sun, 22 Feb 2009 18:22:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756489AbZBVXQg (ORCPT ); Sun, 22 Feb 2009 18:16:36 -0500 Received: from gir.skynet.ie ([193.1.99.77]:39511 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756196AbZBVXQa (ORCPT ); Sun, 22 Feb 2009 18:16:30 -0500 From: Mel Gorman To: Mel Gorman , Linux Memory Management List Cc: Pekka Enberg , Rik van Riel , KOSAKI Motohiro , Christoph Lameter , Johannes Weiner , Nick Piggin , Linux Kernel Mailing List , Lin Ming , Zhang Yanmin Subject: [PATCH 16/20] Do not setup zonelist cache when there is only one node Date: Sun, 22 Feb 2009 23:17:25 +0000 Message-Id: <1235344649-18265-17-git-send-email-mel@csn.ul.ie> X-Mailer: git-send-email 1.5.6.5 In-Reply-To: <1235344649-18265-1-git-send-email-mel@csn.ul.ie> References: <1235344649-18265-1-git-send-email-mel@csn.ul.ie> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is a zonelist cache which is used to track zones that are not in the allowed cpuset or found to be recently full. This is to reduce cache footprint on large machines. On smaller machines, it just incurs cost for no gain. This patch only uses the zonelist cache when there are NUMA nodes. Signed-off-by: Mel Gorman --- mm/page_alloc.c | 12 +++++++++--- 1 files changed, 9 insertions(+), 3 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 9adafba..9e16aec 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1481,9 +1481,15 @@ this_zone_full: zlc_mark_zone_full(zonelist, z); try_next_zone: if (NUMA_BUILD && !did_zlc_setup) { - /* we do zlc_setup after the first zone is tried */ - allowednodes = zlc_setup(zonelist, alloc_flags); - zlc_active = 1; + /* + * we do zlc_setup after the first zone is tried + * but only if there are multiple nodes to make + * it worthwhile + */ + if (num_online_nodes() > 1) { + allowednodes = zlc_setup(zonelist, alloc_flags); + zlc_active = 1; + } did_zlc_setup = 1; } } -- 1.5.6.5