From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [PATCH RFC] memcg: revert kmem.tcp accounting Date: Fri, 12 Sep 2014 14:43:26 -0700 Message-ID: <20140912144326.a8d5153d7c91d220ea89924a@linux-foundation.org> References: <1410535618-9601-1-git-send-email-vdavydov@parallels.com> <20140912171809.GA24469@dhcp22.suse.cz> <20140912175516.GB6298@mtj.dyndns.org> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140912175516.GB6298@mtj.dyndns.org> Sender: owner-linux-mm@kvack.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Tejun Heo Cc: Michal Hocko , 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 , Greg Thelen , Eric Dumazet , "Eric W. Biederman" On Sat, 13 Sep 2014 02:55:16 +0900 Tejun Heo wrote: > 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. 17 files changed, 51 insertions(+), 761 deletions(-) Sob. Is there a convenient way of disabling the whole thing and adding a please-tell-us printk? If nobody tells us for a year or two then zap. -- 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