From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932441Ab2GKTSH (ORCPT ); Wed, 11 Jul 2012 15:18:07 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:45487 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932191Ab2GKTSF (ORCPT ); Wed, 11 Jul 2012 15:18:05 -0400 Message-ID: <4FFDD12B.1050909@linux.vnet.ibm.com> Date: Wed, 11 Jul 2012 14:16:59 -0500 From: Seth Jennings User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120615 Thunderbird/13.0.1 MIME-Version: 1.0 To: Minchan Kim CC: Greg Kroah-Hartman , Andrew Morton , Dan Magenheimer , Konrad Rzeszutek Wilk , Nitin Gupta , Robert Jennings , linux-mm@kvack.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/4] zsmalloc improvements References: <1341263752-10210-1-git-send-email-sjenning@linux.vnet.ibm.com> <4FFD2524.2050300@kernel.org> In-Reply-To: <4FFD2524.2050300@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12071119-7606-0000-0000-000001ECDCEE Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/11/2012 02:03 AM, Minchan Kim wrote: > Today, I tested zsmapbench in my embedded board(ARM). > tlb-flush is 30% faster than copy-based so it's always not win. > I think it depends on CPU speed/cache size. After you pointed this out, I decided to test this on my Raspberry Pi, the only ARM system I have that is open enough for me to work with. I pulled some of the cycle counting stuff out of arch/arm/kernel/perf_event_v6.c. I've pushed that code to the github repo. git://github.com/spartacus06/zsmapbench.git My results were in agreement with your findings. I got 2040 cycles/map for the copy method and 947 cycles/map for the page-table method. I think memory speed is playing a big roll in the difference. I agree that the page-table method should be restored since the performance difference is so significant on ARM, a platform that benefits a lot from memory compression IMHO. Still, the question remains how to implement the selection logic, since not all archs that support the page-table method will necessarily perform better with it. Thanks, Seth From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx163.postini.com [74.125.245.163]) by kanga.kvack.org (Postfix) with SMTP id A8C6B6B005D for ; Wed, 11 Jul 2012 15:18:18 -0400 (EDT) Received: from /spool/local by e36.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 11 Jul 2012 13:18:14 -0600 Received: from d03relay03.boulder.ibm.com (d03relay03.boulder.ibm.com [9.17.195.228]) by d03dlp01.boulder.ibm.com (Postfix) with ESMTP id 2FE381FF004C for ; Wed, 11 Jul 2012 19:17:24 +0000 (WET) Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay03.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q6BJH6bN042120 for ; Wed, 11 Jul 2012 13:17:17 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q6BJH4FH030982 for ; Wed, 11 Jul 2012 13:17:04 -0600 Message-ID: <4FFDD12B.1050909@linux.vnet.ibm.com> Date: Wed, 11 Jul 2012 14:16:59 -0500 From: Seth Jennings MIME-Version: 1.0 Subject: Re: [PATCH 0/4] zsmalloc improvements References: <1341263752-10210-1-git-send-email-sjenning@linux.vnet.ibm.com> <4FFD2524.2050300@kernel.org> In-Reply-To: <4FFD2524.2050300@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: Greg Kroah-Hartman , Andrew Morton , Dan Magenheimer , Konrad Rzeszutek Wilk , Nitin Gupta , Robert Jennings , linux-mm@kvack.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org On 07/11/2012 02:03 AM, Minchan Kim wrote: > Today, I tested zsmapbench in my embedded board(ARM). > tlb-flush is 30% faster than copy-based so it's always not win. > I think it depends on CPU speed/cache size. After you pointed this out, I decided to test this on my Raspberry Pi, the only ARM system I have that is open enough for me to work with. I pulled some of the cycle counting stuff out of arch/arm/kernel/perf_event_v6.c. I've pushed that code to the github repo. git://github.com/spartacus06/zsmapbench.git My results were in agreement with your findings. I got 2040 cycles/map for the copy method and 947 cycles/map for the page-table method. I think memory speed is playing a big roll in the difference. I agree that the page-table method should be restored since the performance difference is so significant on ARM, a platform that benefits a lot from memory compression IMHO. Still, the question remains how to implement the selection logic, since not all archs that support the page-table method will necessarily perform better with it. Thanks, Seth -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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