From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f181.google.com (mail-pd0-f181.google.com [209.85.192.181]) by kanga.kvack.org (Postfix) with ESMTP id CB10A6B0039 for ; Fri, 12 Sep 2014 13:55:23 -0400 (EDT) Received: by mail-pd0-f181.google.com with SMTP id w10so1713649pde.12 for ; Fri, 12 Sep 2014 10:55:23 -0700 (PDT) Received: from mail-pd0-x229.google.com (mail-pd0-x229.google.com [2607:f8b0:400e:c02::229]) by mx.google.com with ESMTPS id oe1si9120083pbc.212.2014.09.12.10.55.22 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 12 Sep 2014 10:55:23 -0700 (PDT) Received: by mail-pd0-f169.google.com with SMTP id fp1so1717844pdb.14 for ; Fri, 12 Sep 2014 10:55:22 -0700 (PDT) Date: Sat, 13 Sep 2014 02:55:16 +0900 From: Tejun Heo Subject: Re: [PATCH RFC] memcg: revert kmem.tcp accounting Message-ID: <20140912175516.GB6298@mtj.dyndns.org> References: <1410535618-9601-1-git-send-email-vdavydov@parallels.com> <20140912171809.GA24469@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140912171809.GA24469@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Vladimir Davydov , linux-kernel@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org, Li Zefan , "David S. Miller" , Johannes Weiner , Kamezawa Hiroyuki , Glauber Costa , Pavel Emelianov , Andrew Morton , Greg Thelen , Eric Dumazet , "Eric W. Biederman" Hello, guys. On Fri, Sep 12, 2014 at 07:18:09PM +0200, Michal Hocko wrote: > On Fri 12-09-14 19:26:58, Vladimir Davydov wrote: > > memory.kmem.tcp.limit_in_bytes works as the system-wide tcp_mem sysctl, > > but per memory cgroup. While the existence of the latter is justified > > (it prevents the system from becoming unusable due to uncontrolled tcp > > buffers growth) the reason why we need such a knob in containers isn't > > clear to me. > > Parallels was the primary driver for this change. I haven't heard of > anybody using the feature other than Parallels. I also remember there > was a strong push for this feature before it was merged besides there > were some complains at the time. I do not remember details (and I am > one half way gone for the weekend now) so I do not have pointers to > discussions. > > I would love to get rid of the code and I am pretty sure that networking > people would love this go even more. I didn't plan to provide kmem.tcp.* > knobs for the cgroups v2 interface but getting rid of it altogether > sounds even better. I am just not sure whether some additional users > grown over time. > Nevertheless I am really curious. What has changed that Parallels is not > interested in kmem.tcp anymore? So, I'd love to see this happen too but I don't think we can do this. People use published interface. The usages might be utterly one-off and mental but let's please not underestimate the sometimes senseless creativity found in the wild. We simply can't remove a bunch of control knobs like this. Thanks. -- tejun -- 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