From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f198.google.com (mail-wr0-f198.google.com [209.85.128.198]) by kanga.kvack.org (Postfix) with ESMTP id 357F26B0038 for ; Mon, 15 Jan 2018 07:46:56 -0500 (EST) Received: by mail-wr0-f198.google.com with SMTP id 62so4720985wrf.8 for ; Mon, 15 Jan 2018 04:46:56 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id i186si6797444wmf.240.2018.01.15.04.46.54 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 15 Jan 2018 04:46:54 -0800 (PST) Date: Mon, 15 Jan 2018 13:46:52 +0100 From: Michal Hocko Subject: Re: [PATCH v4] mm/memcg: try harder to decrease [memory,memsw].limit_in_bytes Message-ID: <20180115124652.GB22473@dhcp22.suse.cz> References: <20180109152622.31ca558acb0cc25a1b14f38c@linux-foundation.org> <20180110124317.28887-1-aryabinin@virtuozzo.com> <20180111104239.GZ1732@dhcp22.suse.cz> <4a8f667d-c2ae-e3df-00fd-edc01afe19e1@virtuozzo.com> <20180111124629.GA1732@dhcp22.suse.cz> <20180111162947.GG1732@dhcp22.suse.cz> <560a77b5-02d7-cbae-35f3-0b20a1c384c2@virtuozzo.com> <20180112122405.GK1732@dhcp22.suse.cz> <7d1b5bfb-f602-8cf4-2de6-dd186484e55c@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7d1b5bfb-f602-8cf4-2de6-dd186484e55c@virtuozzo.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrey Ryabinin Cc: Andrew Morton , Johannes Weiner , Vladimir Davydov , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Shakeel Butt On Mon 15-01-18 15:30:59, Andrey Ryabinin wrote: > > > On 01/12/2018 03:24 PM, Michal Hocko wrote: > > On Fri 12-01-18 00:59:38, Andrey Ryabinin wrote: > >> On 01/11/2018 07:29 PM, Michal Hocko wrote: > > [...] > >>> I do not think so. Consider that this reclaim races with other > >>> reclaimers. Now you are reclaiming a large chunk so you might end up > >>> reclaiming more than necessary. SWAP_CLUSTER_MAX would reduce the over > >>> reclaim to be negligible. > >>> > >> > >> I did consider this. And I think, I already explained that sort of race in previous email. > >> Whether "Task B" is really a task in cgroup or it's actually a bunch of reclaimers, > >> doesn't matter. That doesn't change anything. > > > > I would _really_ prefer two patches here. The first one removing the > > hard coded reclaim count. That thing is just dubious at best. If you > > _really_ think that the higher reclaim target is meaningfull then make > > it a separate patch. I am not conviced but I will not nack it it either. > > But it will make our life much easier if my over reclaim concern is > > right and we will need to revert it. Conceptually those two changes are > > independent anywa. > > > > Ok, fair point. But what about livelock than? Don't you think that we should > go back to something like in V1 patch to prevent it? I am not sure what do you mean by the livelock here. -- Michal Hocko SUSE Labs -- 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