From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e1.ny.us.ibm.com (e1.ny.us.ibm.com [32.97.182.141]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e1.ny.us.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 3A4A6B7BA8 for ; Wed, 14 Oct 2009 02:49:06 +1100 (EST) Received: from d01relay04.pok.ibm.com (d01relay04.pok.ibm.com [9.56.227.236]) by e1.ny.us.ibm.com (8.14.3/8.13.1) with ESMTP id n9DFliSE023099 for ; Tue, 13 Oct 2009 11:47:44 -0400 Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by d01relay04.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id n9DFn2Ub257028 for ; Tue, 13 Oct 2009 11:49:02 -0400 Received: from d01av04.pok.ibm.com (loopback [127.0.0.1]) by d01av04.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id n9DFmiYe024441 for ; Tue, 13 Oct 2009 11:49:01 -0400 Date: Tue, 13 Oct 2009 10:48:41 -0500 From: Robert Jennings To: Mel Gorman Subject: Re: [PATCH 1/2][v2] mm: add notifier in pageblock isolation for balloon drivers Message-ID: <20091013154841.GB18305@austin.ibm.com> References: <20091002184458.GC4908@austin.ibm.com> <20091008163449.00dce972.akpm@linux-foundation.org> <20091009202304.GB19114@austin.ibm.com> <20091009204326.GH24845@csn.ul.ie> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20091009204326.GH24845@csn.ul.ie> Cc: linux-mm@kvack.org, Gerald Schaefer , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Martin Schwidefsky , Badari Pulavarty , Brian King , Paul Mackerras , Andrew Morton , Ingo Molnar , KAMEZAWA Hiroyuki List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Oct 09, 2009 at 21:43:26 +0100, Mal Gorman wrote: > As you have tested this recently, would you be willing to post the > results? While it's not a requirement of the patch, it would be nice to have > an idea of how the effectiveness of memory hot-remove is improved when used > with the powerpc balloon. This might convince others developers for balloons > to register with the notifier. I did ten test runs without my patches and ten test runs with my patches on a 2.6.32-rc3 kernel. Without the patch: 6 out of 10 memory-remove operations without the patch removed 1 LMB (64Mb), the rest of the memory-remove attempts failed to remove any LMBs. With the patch: All of the memory-remove operations removed some LMBs. The average removed was just over 11 LMBs (704Mb) per attempt. Linux was given 2Gb of memory. During the test runs the average memory in use was 140Mb, not including cache and buffers, and the average amount consumed by the balloon was 1217Mb. The system was idle while the memory remove operation was performed. After each attempt the system was rebooted and allowed ~10 minutes to settle after boot. With a 2Gb configuration on POWER the LMB size is 64Mb. The drmgr command (part of powerpc-utils) was used to remove memory by LBM, just as an end-user would. Below is a list of the runs and the number of LMBs removed. Stock kernel (v2.6.32-rc3) -------------------------- LMBs Used kb Loaned kb removed 0 135232 1257280 0 151168 1231744 1 152128 1234176 1 150976 1239232 1 151808 1232064 0 136064 1249152 0 137088 1246976 1 135296 1289984 1 136384 1263104 1 152960 1243904 ======================= 0.60 143910 1248762 Average 0.49 7929 16960 StdDev Patched kernel -------------------------- LMBs Used kb Loaned kb removed 12 134336 1294336 10 152192 1250432 9 152832 1235520 15 153152 1237952 12 152320 1232704 13 135360 1252224 11 154176 1237056 10 153920 1243264 10 150720 1236416 13 151040 1230848 ======================= 11.50 149005 1245075 Average 1.75 7158 17738 StdDev Regards, Robert Jennings