From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id 27B636B0083 for ; Sun, 22 Feb 2009 18:16:32 -0500 (EST) From: Mel Gorman 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> 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: owner-linux-mm@kvack.org 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 List-ID: 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 -- 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