From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id 8CB996B0008 for ; Mon, 23 Apr 2018 11:29:33 -0400 (EDT) Received: by mail-pf0-f197.google.com with SMTP id d13so10726014pfn.21 for ; Mon, 23 Apr 2018 08:29:33 -0700 (PDT) Received: from mail5.wrs.com (mail5.windriver.com. [192.103.53.11]) by mx.google.com with ESMTPS id t25si10935715pfh.101.2018.04.23.08.29.31 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 23 Apr 2018 08:29:32 -0700 (PDT) Message-ID: <5ADDFBD1.7010009@windriver.com> Date: Mon, 23 Apr 2018 11:29:21 -0400 From: Chris Friesen MIME-Version: 1.0 Subject: Re: per-NUMA memory limits in mem cgroup? References: <5ADA26AB.6080209@windriver.com> <20180422124648.GD17484@dhcp22.suse.cz> In-Reply-To: <20180422124648.GD17484@dhcp22.suse.cz> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: "cgroups@vger.kernel.org" , linux-mm@kvack.org, Johannes Weiner , Vladimir Davydov On 04/22/2018 08:46 AM, Michal Hocko wrote: > On Fri 20-04-18 11:43:07, Chris Friesen wrote: >> The specific scenario I'm considering is that of a hypervisor host. I have >> system management stuff running on the host that may need more than one >> core, and currently these host tasks might be affined to cores from multiple >> NUMA nodes. I'd like to put a cap on how much memory the host tasks can >> allocate from each NUMA node in order to ensure that there is a guaranteed >> amount of memory available for VMs on each NUMA node. >> >> Is this possible, or are the knobs just not there? > > Not possible right now. What would be the policy when you reach the > limit on one node? Fallback to other nodes? What if those hit the limit > as well? OOM killer or an allocation failure? I'd envision it working exactly the same as the current memory cgroup, but with the ability to specify optional per-NUMA-node limits in addition to system-wide. Chris