From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754197Ab1EPVKb (ORCPT ); Mon, 16 May 2011 17:10:31 -0400 Received: from smtp-out.google.com ([74.125.121.67]:42252 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753498Ab1EPVK3 (ORCPT ); Mon, 16 May 2011 17:10:29 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=google.com; s=beta; h=date:from:x-x-sender:to:cc:subject:in-reply-to:message-id :references:user-agent:mime-version:content-type; b=PL4CdAF4WZpauAUO4r29zHVzSdPlbKErEzN6cuhxVQ37X67aHgs2X7aGnI8tgw7KJQ 13iveN6aAH9OqsbJY3dg== Date: Mon, 16 May 2011 14:10:24 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Mel Gorman cc: Andrew Morton , James Bottomley , Colin King , Raghavendra D Prabhu , Jan Kara , Chris Mason , Christoph Lameter , Pekka Enberg , Rik van Riel , Johannes Weiner , linux-fsdevel , linux-mm , linux-kernel , linux-ext4 Subject: Re: [PATCH 2/4] mm: slub: Do not wake kswapd for SLUBs speculative high-order allocations In-Reply-To: <1305295404-12129-3-git-send-email-mgorman@suse.de> Message-ID: References: <1305295404-12129-1-git-send-email-mgorman@suse.de> <1305295404-12129-3-git-send-email-mgorman@suse.de> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 13 May 2011, Mel Gorman wrote: > To avoid locking and per-cpu overhead, SLUB optimisically uses > high-order allocations and falls back to lower allocations if they > fail. However, by simply trying to allocate, kswapd is woken up to > start reclaiming at that order. On a desktop system, two users report > that the system is getting locked up with kswapd using large amounts > of CPU. Using SLAB instead of SLUB made this problem go away. > > This patch prevents kswapd being woken up for high-order allocations. > Testing indicated that with this patch applied, the system was much > harder to hang and even when it did, it eventually recovered. > > Signed-off-by: Mel Gorman Acked-by: David Rientjes From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with ESMTP id 077C690010D for ; Mon, 16 May 2011 17:10:29 -0400 (EDT) Received: from wpaz21.hot.corp.google.com (wpaz21.hot.corp.google.com [172.24.198.85]) by smtp-out.google.com with ESMTP id p4GLASF2032385 for ; Mon, 16 May 2011 14:10:28 -0700 Received: from pvg16 (pvg16.prod.google.com [10.241.210.144]) by wpaz21.hot.corp.google.com with ESMTP id p4GLAQXD023230 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for ; Mon, 16 May 2011 14:10:27 -0700 Received: by pvg16 with SMTP id 16so3966546pvg.1 for ; Mon, 16 May 2011 14:10:26 -0700 (PDT) Date: Mon, 16 May 2011 14:10:24 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH 2/4] mm: slub: Do not wake kswapd for SLUBs speculative high-order allocations In-Reply-To: <1305295404-12129-3-git-send-email-mgorman@suse.de> Message-ID: References: <1305295404-12129-1-git-send-email-mgorman@suse.de> <1305295404-12129-3-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Andrew Morton , James Bottomley , Colin King , Raghavendra D Prabhu , Jan Kara , Chris Mason , Christoph Lameter , Pekka Enberg , Rik van Riel , Johannes Weiner , linux-fsdevel , linux-mm , linux-kernel , linux-ext4 On Fri, 13 May 2011, Mel Gorman wrote: > To avoid locking and per-cpu overhead, SLUB optimisically uses > high-order allocations and falls back to lower allocations if they > fail. However, by simply trying to allocate, kswapd is woken up to > start reclaiming at that order. On a desktop system, two users report > that the system is getting locked up with kswapd using large amounts > of CPU. Using SLAB instead of SLUB made this problem go away. > > This patch prevents kswapd being woken up for high-order allocations. > Testing indicated that with this patch applied, the system was much > harder to hang and even when it did, it eventually recovered. > > Signed-off-by: Mel Gorman Acked-by: David Rientjes -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org