Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935034Ab3DHRjs (ORCPT ); Mon, 8 Apr 2013 13:39:48 -0400 Received: from e9.ny.us.ibm.com ([32.97.182.139]:37765 "EHLO e9.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762474Ab3DHRjr (ORCPT ); Mon, 8 Apr 2013 13:39:47 -0400 Message-ID: <516300C7.7000008@linux.vnet.ibm.com> Date: Mon, 08 Apr 2013 10:39:19 -0700 From: Cody P Schafer User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130308 Thunderbird/17.0.4 MIME-Version: 1.0 To: Simon Jeons CC: Andrew Morton , Mel Gorman , Linux MM , LKML Subject: Re: [PATCH 1/3] mm/page_alloc: factor out setting of pcp->high and pcp->batch. References: <1365194030-28939-1-git-send-email-cody@linux.vnet.ibm.com> <1365194030-28939-2-git-send-email-cody@linux.vnet.ibm.com> <5160CDD8.3050908@gmail.com> In-Reply-To: <5160CDD8.3050908@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13040817-7182-0000-0000-0000062409AC Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1250 Lines: 28 On 04/06/2013 06:37 PM, Simon Jeons wrote: > Hi Cody, > On 04/06/2013 04:33 AM, Cody P Schafer wrote: >> Creates pageset_set_batch() for use in setup_pageset(). >> pageset_set_batch() imitates the functionality of >> setup_pagelist_highmark(), but uses the boot time >> (percpu_pagelist_fraction == 0) calculations for determining ->high > > Why need adjust pcp->high, pcp->batch during system running? What's the > requirement? > There is currently a sysctl (which I patch later in this series) which allows adjusting the ->high mark (and, indirectly, ->batch). Additionally, memory hotplug changes ->high and ->batch due to the zone size changing (essentially, zone->managed_pages and zone->present_pages have changed) , meaning that zone_batchsize(), which is used at boot to set ->batch and (indirectly) ->high has a different output. Note that in addition to the 2 users of this functionality mentioned here, I'm currently working on anther resizer of zones (runtime NUMA reconfiguration). -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/