From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61427C43460 for ; Fri, 9 Apr 2021 07:24:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 340D661177 for ; Fri, 9 Apr 2021 07:24:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231674AbhDIHYo (ORCPT ); Fri, 9 Apr 2021 03:24:44 -0400 Received: from mx2.suse.de ([195.135.220.15]:50424 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229703AbhDIHYn (ORCPT ); Fri, 9 Apr 2021 03:24:43 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1617953070; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=3CuiOk6cqvEWVs8EpFm1ZB/VV5Oybfre6iEM0gujwYY=; b=H4OWQuY93sOd2wKm3WVHcYphE9zQySsHIQ3lLQnHVXjXiTp5Z2tGAgTERRG5jUPKPJz+WD aeAYiSW0cSqzDTTLy2KbJpJgWv7DhS+age8yXFSPvW0YTZsIDaZ7PgOaFd1yMcKNYaXUvZ kMvpiEldYW/V/6JgPafaL4NeJ4VBUV0= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id DCA45AF0D; Fri, 9 Apr 2021 07:24:29 +0000 (UTC) Date: Fri, 9 Apr 2021 09:24:28 +0200 From: Michal Hocko To: Shakeel Butt Cc: Yang Shi , Tim Chen , Johannes Weiner , Andrew Morton , Dave Hansen , Ying Huang , Dan Williams , David Rientjes , Linux MM , Cgroups , LKML Subject: Re: [RFC PATCH v1 00/11] Manage the top tier memory in a tiered memory Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 08-04-21 13:29:08, Shakeel Butt wrote: > On Thu, Apr 8, 2021 at 11:01 AM Yang Shi wrote: [...] > > The low priority jobs should be able to be restricted by cpuset, for > > example, just keep them on second tier memory nodes. Then all the > > above problems are gone. Yes, if the aim is to isolate some users from certain numa node then cpuset is a good fit but as Shakeel says this is very likely not what this work is aiming for. > Yes that's an extreme way to overcome the issue but we can do less > extreme by just (hard) limiting the top tier usage of low priority > jobs. Per numa node high/hard limit would help with a more fine grained control. The configuration would be tricky though. All low priority memcgs would have to be carefully configured to leave enough for your important processes. That includes also memory which is not accounted to any memcg. The behavior of those limits would be quite tricky for OOM situations as well due to a lack of NUMA aware oom killer. -- Michal Hocko SUSE Labs