From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751391Ab2KPHW3 (ORCPT ); Fri, 16 Nov 2012 02:22:29 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:43423 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751338Ab2KPHW2 (ORCPT ); Fri, 16 Nov 2012 02:22:28 -0500 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.8.4 Message-ID: <50A5E997.6060002@jp.fujitsu.com> Date: Fri, 16 Nov 2012 16:21:59 +0900 From: Kamezawa Hiroyuki User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:16.0) Gecko/20121026 Thunderbird/16.0.2 MIME-Version: 1.0 To: Glauber Costa CC: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Tejun Heo , Michal Hocko , Johannes Weiner , Christoph Lameter , Pekka Enberg Subject: Re: [PATCH 5/7] memcg: get rid of once-per-second cache shrinking for dead memcgs References: <1352948093-2315-1-git-send-email-glommer@parallels.com> <1352948093-2315-6-git-send-email-glommer@parallels.com> <50A4B8C8.6020202@jp.fujitsu.com> <50A4F289.1090807@parallels.com> <50A5CA16.7070603@jp.fujitsu.com> <50A5E73F.8030201@parallels.com> In-Reply-To: <50A5E73F.8030201@parallels.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (2012/11/16 16:11), Glauber Costa wrote: > On 11/16/2012 09:07 AM, Kamezawa Hiroyuki wrote: >> (2012/11/15 22:47), Glauber Costa wrote: >>> On 11/15/2012 01:41 PM, Kamezawa Hiroyuki wrote: >>>> (2012/11/15 11:54), Glauber Costa wrote: >>>>> The idea is to synchronously do it, leaving it up to the shrinking >>>>> facilities in vmscan.c and/or others. Not actively retrying shrinking >>>>> may leave the caches alive for more time, but it will remove the ugly >>>>> wakeups. One would argue that if the caches have free objects but are >>>>> not being shrunk, it is because we don't need that memory yet. >>>>> >>>>> Signed-off-by: Glauber Costa >>>>> CC: Michal Hocko >>>>> CC: Kamezawa Hiroyuki >>>>> CC: Johannes Weiner >>>>> CC: Andrew Morton >>>> >>>> I agree this patch but can we have a way to see the number of unaccounted >>>> zombie cache usage for debugging ? >>>> >>>> Acked-by: KAMEZAWA Hiroyuki >>>> >>> Any particular interface in mind ? >>> >> >> Hmm, it's debug interface and having cgroup file may be bad..... >> If it can be seen in bytes or some, /proc/vmstat ? >> >> out_of_track_slabs xxxxxxx. hm ? >> > > I particularly think that, being this a debug interface, it is also > useful to have an indication of which caches are still in place. This is > because the cache itself, is the best indication we have about the > specific workload that may be keeping it in memory. > > I first thought debugfs could help us probing useful information out of > it, but given all the abuse people inflicted in debugfs... maybe we > could have a file in the root memcg with that information for all > removed memcgs? If we do that, we can go further and list the memcgs > that are pending due to memsw as well. memory.dangling_memcgs ? > Hm, I'm ok with it... others ? Thanks, -Kame From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx178.postini.com [74.125.245.178]) by kanga.kvack.org (Postfix) with SMTP id F00466B002B for ; Fri, 16 Nov 2012 02:22:28 -0500 (EST) Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id 5FAD93EE081 for ; Fri, 16 Nov 2012 16:22:26 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 4299945DE56 for ; Fri, 16 Nov 2012 16:22:26 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 27B3345DE5B for ; Fri, 16 Nov 2012 16:22:26 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 1A1761DB803C for ; Fri, 16 Nov 2012 16:22:26 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.240.81.134]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id C5F171DB803A for ; Fri, 16 Nov 2012 16:22:25 +0900 (JST) Message-ID: <50A5E997.6060002@jp.fujitsu.com> Date: Fri, 16 Nov 2012 16:21:59 +0900 From: Kamezawa Hiroyuki MIME-Version: 1.0 Subject: Re: [PATCH 5/7] memcg: get rid of once-per-second cache shrinking for dead memcgs References: <1352948093-2315-1-git-send-email-glommer@parallels.com> <1352948093-2315-6-git-send-email-glommer@parallels.com> <50A4B8C8.6020202@jp.fujitsu.com> <50A4F289.1090807@parallels.com> <50A5CA16.7070603@jp.fujitsu.com> <50A5E73F.8030201@parallels.com> In-Reply-To: <50A5E73F.8030201@parallels.com> Content-Type: text/plain; charset=ISO-2022-JP Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Glauber Costa Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Tejun Heo , Michal Hocko , Johannes Weiner , Christoph Lameter , Pekka Enberg (2012/11/16 16:11), Glauber Costa wrote: > On 11/16/2012 09:07 AM, Kamezawa Hiroyuki wrote: >> (2012/11/15 22:47), Glauber Costa wrote: >>> On 11/15/2012 01:41 PM, Kamezawa Hiroyuki wrote: >>>> (2012/11/15 11:54), Glauber Costa wrote: >>>>> The idea is to synchronously do it, leaving it up to the shrinking >>>>> facilities in vmscan.c and/or others. Not actively retrying shrinking >>>>> may leave the caches alive for more time, but it will remove the ugly >>>>> wakeups. One would argue that if the caches have free objects but are >>>>> not being shrunk, it is because we don't need that memory yet. >>>>> >>>>> Signed-off-by: Glauber Costa >>>>> CC: Michal Hocko >>>>> CC: Kamezawa Hiroyuki >>>>> CC: Johannes Weiner >>>>> CC: Andrew Morton >>>> >>>> I agree this patch but can we have a way to see the number of unaccounted >>>> zombie cache usage for debugging ? >>>> >>>> Acked-by: KAMEZAWA Hiroyuki >>>> >>> Any particular interface in mind ? >>> >> >> Hmm, it's debug interface and having cgroup file may be bad..... >> If it can be seen in bytes or some, /proc/vmstat ? >> >> out_of_track_slabs xxxxxxx. hm ? >> > > I particularly think that, being this a debug interface, it is also > useful to have an indication of which caches are still in place. This is > because the cache itself, is the best indication we have about the > specific workload that may be keeping it in memory. > > I first thought debugfs could help us probing useful information out of > it, but given all the abuse people inflicted in debugfs... maybe we > could have a file in the root memcg with that information for all > removed memcgs? If we do that, we can go further and list the memcgs > that are pending due to memsw as well. memory.dangling_memcgs ? > Hm, I'm ok with it... others ? 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/ . Don't email: email@kvack.org