From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with ESMTP id 2CE206B004D for ; Fri, 28 Aug 2009 11:10:15 -0400 (EDT) Received: from d28relay05.in.ibm.com (d28relay05.in.ibm.com [9.184.220.62]) by e28smtp05.in.ibm.com (8.14.3/8.13.1) with ESMTP id n7SFADkp016550 for ; Fri, 28 Aug 2009 20:40:13 +0530 Received: from d28av05.in.ibm.com (d28av05.in.ibm.com [9.184.220.67]) by d28relay05.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id n7SFADTo2257028 for ; Fri, 28 Aug 2009 20:40:13 +0530 Received: from d28av05.in.ibm.com (loopback [127.0.0.1]) by d28av05.in.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id n7SFADPO000789 for ; Sat, 29 Aug 2009 01:10:13 +1000 Date: Fri, 28 Aug 2009 20:40:11 +0530 From: Balbir Singh Subject: Re: [RFC][PATCH 2/5] memcg: uncharge in batched manner Message-ID: <20090828151011.GS4889@balbir.in.ibm.com> Reply-To: balbir@linux.vnet.ibm.com References: <20090828132015.10a42e40.kamezawa.hiroyu@jp.fujitsu.com> <20090828132438.b33828bc.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20090828132438.b33828bc.kamezawa.hiroyu@jp.fujitsu.com> 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" List-ID: * KAMEZAWA Hiroyuki [2009-08-28 13:24:38]: > > In massive parallel enviroment, res_counter can be a performance bottleneck. > This patch is a trial for reducing lock contention. > One strong techinque to reduce lock contention is reducing calls by > batching some amount of calls int one. > > Considering charge/uncharge chatacteristic, > - charge is done one by one via demand-paging. > - uncharge is done by > - in chunk at munmap, truncate, exit, execve... > - one by one via vmscan/paging. > > It seems we hace a chance to batched-uncharge. > This patch is a base patch for batched uncharge. For avoiding > scattering memcg's structure, this patch adds memcg batch uncharge > information to the task. please see start/end usage in next patch. > Overall it is a very good idea, can't we do the uncharge at the poin tof unmap_vmas, exit_mmap, etc so that we don't have to keep additional data structures around. -- Balbir -- 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