From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta8.messagelabs.com (mail6.bemta8.messagelabs.com [216.82.243.55]) by kanga.kvack.org (Postfix) with ESMTP id 8118D900149 for ; Tue, 4 Oct 2011 20:31:37 -0400 (EDT) Received: from m1.gw.fujitsu.co.jp (unknown [10.0.50.71]) by fgwmail5.fujitsu.co.jp (Postfix) with ESMTP id 808A53EE0CB for ; Wed, 5 Oct 2011 09:31:33 +0900 (JST) Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 5E73045DE54 for ; Wed, 5 Oct 2011 09:31:33 +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 3B82945DE55 for ; Wed, 5 Oct 2011 09:31:33 +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 270F91DB8057 for ; Wed, 5 Oct 2011 09:31:33 +0900 (JST) Received: from m106.s.css.fujitsu.com (m106.s.css.fujitsu.com [10.240.81.146]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id D62B41DB804D for ; Wed, 5 Oct 2011 09:31:32 +0900 (JST) Date: Wed, 5 Oct 2011 09:29:54 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH v5 0/8] per-cgroup tcp buffer pressure settings Message-Id: <20111005092954.718a0c29.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <1317730680-24352-1-git-send-email-glommer@parallels.com> References: <1317730680-24352-1-git-send-email-glommer@parallels.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Glauber Costa Cc: linux-kernel@vger.kernel.org, paul@paulmenage.org, lizf@cn.fujitsu.com, ebiederm@xmission.com, davem@davemloft.net, gthelen@google.com, netdev@vger.kernel.org, linux-mm@kvack.org, kirill@shutemov.name, avagin@parallels.com, devel@openvz.org On Tue, 4 Oct 2011 16:17:52 +0400 Glauber Costa wrote: > [[ v3: merge Kirill's suggestions, + a destroy-related bugfix ]] > [[ v4: Fix a bug with non-mounted cgroups + disallow task movement ]] > [[ v5: Compile bug with modular ipv6 + tcp files in bytes ]] > > Kame, Kirill, > > I am submitting this again merging most of your comments. I've decided to > leave some of them out: > * I am not using res_counters for allocated_memory. Besides being more > expensive than what we need, to make it work in a nice way, we'd have > to change the !cgroup code, including other protocols than tcp. Also, > > * I am not using failcnt and max_usage_in_bytes for it. I believe the value > of those lies more in the allocation than in the pressure control. Besides, > fail conditions lie mostly outside of the memory cgroup's control. (Actually, > a soft_limit makes a lot of sense, and I do plan to introduce it in a follow > up series) > > If you agree with the above, and there are any other pressing issues, let me > know and I will address them ASAP. Otherwise, let's discuss it. I'm always open. > I'm not familar with reuqirements of users. So, I appreciate your choices. What I adivse you here is taking a deep breath. Making new version every day is not good for reviewing process ;) (It's now -rc8 and merge will not be so quick, anyway.) At this stage, my concern is view of interfaces and documenation, and future plans. Let me give a try explanation by myself. (Correct me ;) I added some questions but I'm sorry you've already answered. New interfaces are 5 files. All files exists only for non-root memory cgroup. 1. memory.independent_kmem_limit 2. memory.kmem.usage_in_bytes 3. memory.kmem.limit_in_bytes 4. memory.kmem.tcp.limit_in_bytes 5. memory.kmem.tcp.usage_in_bytes * memory.independent_kmem_limit If 1, kmem_limit_in_bytes/kmem_usage_in_bytes works. If 0, kmem_limit_in_bytes/kmem_usage_in_bytes doesn't work and all kmem usages are controlled under memory.limit_in_bytes. Question: - What happens when parent/chidlren cgroup has different indepedent_kmem_limit ? - What happens at creating a new cgroup with use_hierarchy==1. * memory.kmem_limit_in_bytes/memory.kmem.tcp.limit_in_bytes Both files works independently for _Now_. And memory.kmem_usage_in_bytes and memory.kmem_tcp.usage_in_bytes has no relationships. In future plan, kmem.usage_in_bytes should includes tcp.kmem_usage_in_bytes. And kmem.limit_in_bytes should be the limiation of sum of all kmem.xxxx.limit_in_bytes. Question: - Why this integration is difficult ? Can't tcp-limit-code borrows some amount of charges in batch from kmem_limit and use it ? - Don't you need a stat file to indicate "tcp memory pressure works!" ? It can be obtained already ? 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