From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751382AbdCPHe3 (ORCPT ); Thu, 16 Mar 2017 03:34:29 -0400 Received: from mga01.intel.com ([192.55.52.88]:55729 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751037AbdCPHe1 (ORCPT ); Thu, 16 Mar 2017 03:34:27 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,170,1486454400"; d="scan'208";a="76010852" Date: Thu, 16 Mar 2017 15:34:03 +0800 From: Aaron Lu To: Michal Hocko Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Dave Hansen , Tim Chen , Andrew Morton , Ying Huang Subject: Re: [PATCH v2 0/5] mm: support parallel free of memory Message-ID: <20170316073403.GE1661@aaronlu.sh.intel.com> References: <1489568404-7817-1-git-send-email-aaron.lu@intel.com> <20170315141813.GB32626@dhcp22.suse.cz> <20170315154406.GF2442@aaronlu.sh.intel.com> <20170315162843.GA27197@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170315162843.GA27197@dhcp22.suse.cz> User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 15, 2017 at 05:28:43PM +0100, Michal Hocko wrote: ... ... > After all the amount of the work to be done is the same we just risk > more lock contentions, unexpected CPU usage etc. I start to realize this is a good question. I guess max_active=4 produced almost the best result(max_active=8 is only slightly better) is due to the test box is a 4 node machine and therefore, there are 4 zone->lock to contend(let's ignore those tiny zones only available in node 0). I'm going to test on a EP to see if max_active=2 will suffice to produce a good enough result. If so, the proper default number should be the number of nodes. Thanks. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id 6DA876B0388 for ; Thu, 16 Mar 2017 03:33:54 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id y17so77391461pgh.2 for ; Thu, 16 Mar 2017 00:33:54 -0700 (PDT) Received: from mga09.intel.com (mga09.intel.com. [134.134.136.24]) by mx.google.com with ESMTPS id d124si4418543pgc.413.2017.03.16.00.33.53 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 Mar 2017 00:33:53 -0700 (PDT) Date: Thu, 16 Mar 2017 15:34:03 +0800 From: Aaron Lu Subject: Re: [PATCH v2 0/5] mm: support parallel free of memory Message-ID: <20170316073403.GE1661@aaronlu.sh.intel.com> References: <1489568404-7817-1-git-send-email-aaron.lu@intel.com> <20170315141813.GB32626@dhcp22.suse.cz> <20170315154406.GF2442@aaronlu.sh.intel.com> <20170315162843.GA27197@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170315162843.GA27197@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Dave Hansen , Tim Chen , Andrew Morton , Ying Huang On Wed, Mar 15, 2017 at 05:28:43PM +0100, Michal Hocko wrote: ... ... > After all the amount of the work to be done is the same we just risk > more lock contentions, unexpected CPU usage etc. I start to realize this is a good question. I guess max_active=4 produced almost the best result(max_active=8 is only slightly better) is due to the test box is a 4 node machine and therefore, there are 4 zone->lock to contend(let's ignore those tiny zones only available in node 0). I'm going to test on a EP to see if max_active=2 will suffice to produce a good enough result. If so, the proper default number should be the number of nodes. Thanks. -- 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