From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id 3BDDF6B0082 for ; Thu, 21 Jan 2010 10:30:40 -0500 (EST) Received: from d23relay04.au.ibm.com (d23relay04.au.ibm.com [202.81.31.246]) by e23smtp06.au.ibm.com (8.14.3/8.13.1) with ESMTP id o0LFUXaw008602 for ; Fri, 22 Jan 2010 02:30:33 +1100 Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay04.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o0LFPrnw1622182 for ; Fri, 22 Jan 2010 02:25:53 +1100 Received: from d23av04.au.ibm.com (loopback [127.0.0.1]) by d23av04.au.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id o0LFUY5P021581 for ; Fri, 22 Jan 2010 02:30:34 +1100 Message-ID: <4B587317.6060404@linux.vnet.ibm.com> Date: Thu, 21 Jan 2010 21:00:31 +0530 From: Balbir Singh Reply-To: balbir@linux.vnet.ibm.com MIME-Version: 1.0 Subject: Re: [PATCH mmotm] memcg use generic percpu allocator instead of private one References: <20100120161825.15c372ac.kamezawa.hiroyu@jp.fujitsu.com> <4B56CEF0.2040406@linux.vnet.ibm.com> <20100121110759.250ed739.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20100121110759.250ed739.kamezawa.hiroyu@jp.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: KAMEZAWA Hiroyuki Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , "nishimura@mxp.nes.nec.co.jp" , kirill@shutemov.name List-ID: On Thursday 21 January 2010 07:37 AM, KAMEZAWA Hiroyuki wrote: > On Wed, 20 Jan 2010 15:07:52 +0530 > Balbir Singh wrote: > >>> This includes no functional changes. >>> >>> Signed-off-by: KAMEZAWA Hiroyuki >> >> >> Before review, could you please post parallel pagefault data on a large >> system, since root now uses these per cpu counters and its overhead is >> now dependent on these counters. Also the data read from root cgroup is >> also dependent on these, could you make sure that is not broken. >> > Hmm, I rewrote test program for avoidng mmap_sem. This version does fork() > instead of pthread_create() and meausre parallel-process page fault speed. > > [Before patch] > [root@bluextal memory]# /root/bin/perf stat -e page-faults,cache-misses --repeat 5 ./multi-fault-fork 8 > > Performance counter stats for './multi-fault-fork 8' (5 runs): > > 45256919 page-faults ( +- 0.851% ) > 602230144 cache-misses ( +- 0.187% ) > > 61.020533723 seconds time elapsed ( +- 0.002% > > [After patch] > [root@bluextal memory]# /root/bin/perf stat -e page-faults,cache-misses --repeat 5 ./multi-fault-fork 8 > > Performance counter stats for './multi-fault-fork 8' (5 runs): > > 46007166 page-faults ( +- 0.339% ) > 599553505 cache-misses ( +- 0.298% ) > > 61.020937843 seconds time elapsed ( +- 0.004% ) > > slightly improved ? But this test program does some extreme behavior and > you can't see difference in real-world applications, I think. > So, I guess this is in error-range in famous (not small) benchmarks. Looks good, please give me a couple of days to test, I'll revert back with numbers and review. -- Three Cheers, Balbir Singh -- 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