From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755960Ab2FZJRt (ORCPT ); Tue, 26 Jun 2012 05:17:49 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:46837 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754850Ab2FZJRr (ORCPT ); Tue, 26 Jun 2012 05:17:47 -0400 Date: Tue, 26 Jun 2012 02:17:45 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Glauber Costa cc: cgroups@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , linux-kernel@vger.kernel.org, Frederic Weisbecker , Pekka Enberg , Michal Hocko , Johannes Weiner , Christoph Lameter , devel@openvz.org, kamezawa.hiroyu@jp.fujitsu.com, Tejun Heo , Suleiman Souhlal Subject: Re: [PATCH 02/11] memcg: Reclaim when more than one page needed. In-Reply-To: <4FE97C20.8010500@parallels.com> Message-ID: References: <1340633728-12785-1-git-send-email-glommer@parallels.com> <1340633728-12785-3-git-send-email-glommer@parallels.com> <4FE960D6.4040409@parallels.com> <4FE97C20.8010500@parallels.com> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 26 Jun 2012, Glauber Costa wrote: > > Nope, have you checked the output of /sys/kernel/slab/.../order when > > running slub? On my workstation 127 out of 316 caches have order-2 or > > higher by default. > > > > Well, this is still on the side of my argument, since this is still a majority > of them being low ordered. Ok, so what happens if I pass slub_min_order=2 on the command line? We never retry? > The code here does not necessarily have to retry - > if I understand it correctly - we just retry for very small allocations > because that is where our likelihood of succeeding is. > Well, the comment for NR_PAGES_TO_RETRY says /* * We need a number that is small enough to be likely to have been * reclaimed even under pressure, but not too big to trigger unnecessary * retries */ and mmzone.h says /* * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed * costly to service. That is between allocation orders which should * coalesce naturally under reasonable reclaim pressure and those which * will not. */ #define PAGE_ALLOC_COSTLY_ORDER 3 so I'm trying to reconcile which one is correct. From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Rientjes Subject: Re: [PATCH 02/11] memcg: Reclaim when more than one page needed. Date: Tue, 26 Jun 2012 02:17:45 -0700 (PDT) Message-ID: References: <1340633728-12785-1-git-send-email-glommer@parallels.com> <1340633728-12785-3-git-send-email-glommer@parallels.com> <4FE960D6.4040409@parallels.com> <4FE97C20.8010500@parallels.com> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=date:from:x-x-sender:to:cc:subject:in-reply-to:message-id :references:user-agent:mime-version:content-type; bh=ZRSNLiWPt0IiVRG0SzGeFyXLdio8QkIovvQZEXu8x7g=; b=H5Pye0d3LPVoOZpQ730cIg2Fa+/dRL0UvB7ve/9b2Y0sNCP1tiJQgyi9zAl7VWFRyZ iaR0nUfd8bOHja2TytH1c0U2nT4UO6OG3lpvrdb7LT/tQ93M8e5InkXC2toF9OWyGlap /P02gXn80mBHEkyAy1TsJyUGERWye47Mjb/yMzEtn7i5w6QLSY2LrxPlPYnRjaXb4cZU 8YCY6otbtNdWCntU6KGF5DlS8OLogBDLW5IBYW0syK40NTp3WgiyvRZ+pNzpsArch2Jw LKRsNKhe82s1QTMd3wfVM1bwObV6Ub4iRmobSgTUFUbf2WbtYTVMlR+b2Me4l1Gu4kqY smiQ== In-Reply-To: <4FE97C20.8010500@parallels.com> Sender: owner-linux-mm@kvack.org List-ID: Content-Type: TEXT/PLAIN; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Glauber Costa Cc: cgroups@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , linux-kernel@vger.kernel.org, Frederic Weisbecker , Pekka Enberg , Michal Hocko , Johannes Weiner , Christoph Lameter , devel@openvz.org, kamezawa.hiroyu@jp.fujitsu.com, Tejun Heo , Suleiman Souhlal On Tue, 26 Jun 2012, Glauber Costa wrote: > > Nope, have you checked the output of /sys/kernel/slab/.../order when > > running slub? On my workstation 127 out of 316 caches have order-2 or > > higher by default. > > > > Well, this is still on the side of my argument, since this is still a majority > of them being low ordered. Ok, so what happens if I pass slub_min_order=2 on the command line? We never retry? > The code here does not necessarily have to retry - > if I understand it correctly - we just retry for very small allocations > because that is where our likelihood of succeeding is. > Well, the comment for NR_PAGES_TO_RETRY says /* * We need a number that is small enough to be likely to have been * reclaimed even under pressure, but not too big to trigger unnecessary * retries */ and mmzone.h says /* * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed * costly to service. That is between allocation orders which should * coalesce naturally under reasonable reclaim pressure and those which * will not. */ #define PAGE_ALLOC_COSTLY_ORDER 3 so I'm trying to reconcile which one is correct. -- 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