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 22DA48D0039 for ; Fri, 4 Mar 2011 03:01:19 -0500 (EST) Received: from m3.gw.fujitsu.co.jp (unknown [10.0.50.73]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id 334413EE0BC for ; Fri, 4 Mar 2011 17:01:15 +0900 (JST) Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 1768C45DE59 for ; Fri, 4 Mar 2011 17:01:15 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id F3B5545DE56 for ; Fri, 4 Mar 2011 17:01:14 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id E7F47E08005 for ; Fri, 4 Mar 2011 17:01:14 +0900 (JST) Received: from ml13.s.css.fujitsu.com (ml13.s.css.fujitsu.com [10.249.87.103]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id B15C3E08001 for ; Fri, 4 Mar 2011 17:01:14 +0900 (JST) Date: Fri, 4 Mar 2011 16:54:55 +0900 From: KAMEZAWA Hiroyuki Subject: Re: cgroup memory, blkio and the lovely swapping Message-Id: <20110304165455.d438342a.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20110304083944.22fb612f@sol> References: <20110304083944.22fb612f@sol> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org Cc: Daniel Poelzleithner , linux-mm@kvack.org, containers@lists.linux-foundation.org On Fri, 4 Mar 2011 08:39:44 +0100 Daniel Poelzleithner wrote: > Hi, > > currently when one process causes heavy swapping, the responsiveness of > the hole system suffers greatly. With the small memleak [1] test tool I > wrote, the effect can be experienced very easily, depending on the > delay the lag can become quite large. If I ensure that 10% of the RAM > stay free for free memory and cache, the system never swaps to death. > That works very well, but if accesses to the swap are very heavy, the > system still lags on all other processes, not only the swapping one. > Putting the swapping process into a blkio cgroup with little weight does > not affect the io or swap io from other processes with larger weight in > their group. > > Maybe I'm mistaken, but wouldn't it be the easiest way to get fair > swapping and control to let the pagein respect the blkio.weight value > or even better add a second weight value for swapping io ? > Now, blkio cgroup does work only with synchronous I/O(direct I/O) and never work with swap I/O. And I don't think swap-i/o limit is a blkio matter. Memory cgroup is now developping dirty_ratio for memory cgroup. By that, you can control the number of pages in writeback, in memory cgroup. I think it will work for you. Thanks, -Kame -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org