From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by e28esmtp05.in.ibm.com (8.13.1/8.13.1) with ESMTP id m2BB9bEj002388 for ; Tue, 11 Mar 2008 16:39:37 +0530 Received: from d28av01.in.ibm.com (d28av01.in.ibm.com [9.184.220.63]) by d28relay04.in.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id m2BB9bvp1130620 for ; Tue, 11 Mar 2008 16:39:37 +0530 Received: from d28av01.in.ibm.com (loopback [127.0.0.1]) by d28av01.in.ibm.com (8.13.1/8.13.3) with ESMTP id m2BB9gNR003122 for ; Tue, 11 Mar 2008 11:09:43 GMT Message-ID: <47D66865.1080508@linux.vnet.ibm.com> Date: Tue, 11 Mar 2008 16:39:25 +0530 From: Balbir Singh Reply-To: balbir@linux.vnet.ibm.com MIME-Version: 1.0 Subject: Re: [PATCH] Move memory controller allocations to their own slabs (v2) References: <20080311061836.6664.5072.sendpatchset@localhost.localdomain> <47D63E9D.70500@openvz.org> <47D63FB1.7040502@linux.vnet.ibm.com> <47D6443D.9000904@openvz.org> In-Reply-To: <47D6443D.9000904@openvz.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Pavel Emelyanov Cc: Andrew Morton , Hugh Dickins , Sudhir Kumar , YAMAMOTO Takashi , Paul Menage , lizf@cn.fujitsu.com, linux-kernel@vger.kernel.org, taka@valinux.co.jp, linux-mm@kvack.org, David Rientjes , KAMEZAWA Hiroyuki List-ID: Pavel Emelyanov wrote: > Balbir Singh wrote: >> Pavel Emelyanov wrote: >>> Balbir Singh wrote: >>>> Move the memory controller data structure page_cgroup to its own slab cache. >>>> It saves space on the system, allocations are not necessarily pushed to order >>>> of 2 and should provide performance benefits. Users who disable the memory >>>> controller can also double check that the memory controller is not allocating >>>> page_cgroup's. >>> Can you, please, check how many objects-per-page we have with and >>> without this patch for SLAB and SLUB? >>> >>> Thanks. >> I can for objects-per-page with this patch for SLUB and SLAB. I am not sure >> about what to check for without this patch. The machine is temporarily busy, > > Well, the objects-per-page without the patch is objects-per-page for > according kmalloc cache :) > OK, so here is the data On my 64 bit powerpc system (structure size could be different on other systems) 1. sizeof page_cgroup is 40 bytes which means kmalloc will allocate 64 bytes 2. With 4K pagesize SLAB with HWCACHE_ALIGN, 59 objects are packed per slab 3. With SLUB the value is 102 per slab -- Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL -- 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