From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Weinberger Subject: Re: [RFC][PATCH] oom: Be less verbose if the oom_control event fd has listeners Date: Thu, 05 Jun 2014 17:55:54 +0200 Message-ID: <5390930A.8050504@nod.at> References: <1401976841-3899-1-git-send-email-richard@nod.at> <1401976841-3899-2-git-send-email-richard@nod.at> <20140605150025.GB15939@dhcp22.suse.cz> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140605150025.GB15939@dhcp22.suse.cz> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Michal Hocko Cc: hannes@cmpxchg.org, bsingharora@gmail.com, kamezawa.hiroyu@jp.fujitsu.com, akpm@linux-foundation.org, vdavydov@parallels.com, tj@kernel.org, handai.szj@taobao.com, rientjes@google.com, oleg@redhat.com, rusty@rustcorp.com.au, kirill.shutemov@linux.intel.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org Am 05.06.2014 17:00, schrieb Michal Hocko: > On Thu 05-06-14 16:00:41, Richard Weinberger wrote: >> Don't spam the kernel logs if the oom_control event fd has listeners. >> In this case there is no need to print that much lines as user space >> will anyway notice that the memory cgroup has reached its limit. > > But how do you debug why it is reaching the limit and why a particular > process has been killed? In my case it's always because customer's Java application gone nuts. So I don't really have to debug a lot. ;-) But I can understand your point. > If we are printing too much then OK, let's remove those parts which are > not that useful but hiding information which tells us more about the oom > decision doesn't sound right to me. What about adding a sysctl like "vm.oom_verbose"? By default it would be 1. If set to 0 the full OOM information is only printed out if nobody listens to the event fd. Thanks, //richard