From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wj0-f197.google.com (mail-wj0-f197.google.com [209.85.210.197]) by kanga.kvack.org (Postfix) with ESMTP id EC3956B0033 for ; Thu, 2 Feb 2017 05:14:18 -0500 (EST) Received: by mail-wj0-f197.google.com with SMTP id ez4so2845209wjd.2 for ; Thu, 02 Feb 2017 02:14:18 -0800 (PST) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id h63si6891774wme.168.2017.02.02.02.14.17 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 02 Feb 2017 02:14:17 -0800 (PST) Date: Thu, 2 Feb 2017 11:14:15 +0100 From: Michal Hocko Subject: Re: [RFC PATCH 1/2] mm, vmscan: account the number of isolated pages per zone Message-ID: <20170202101415.GE22806@dhcp22.suse.cz> References: <20170125101957.GA17632@lst.de> <20170125104605.GI32377@dhcp22.suse.cz> <201701252009.IHG13512.OFOJFSVLtOQMFH@I-love.SAKURA.ne.jp> <20170125130014.GO32377@dhcp22.suse.cz> <20170127144906.GB4148@dhcp22.suse.cz> <201701290027.AFB30799.FVtFLOOOJMSHQF@I-love.SAKURA.ne.jp> <20170130085546.GF8443@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170130085546.GF8443@dhcp22.suse.cz> Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: hch@lst.de, mgorman@suse.de, viro@ZenIV.linux.org.uk, linux-mm@kvack.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org On Mon 30-01-17 09:55:46, Michal Hocko wrote: > On Sun 29-01-17 00:27:27, Tetsuo Handa wrote: [...] > > Regarding [1], it helped avoiding the too_many_isolated() issue. I can't > > tell whether it has any negative effect, but I got on the first trial that > > all allocating threads are blocked on wait_for_completion() from flush_work() > > in drain_all_pages() introduced by "mm, page_alloc: drain per-cpu pages from > > workqueue context". There was no warn_alloc() stall warning message afterwords. > > That patch is buggy and there is a follow up [1] which is not sitting in the > mmotm (and thus linux-next) yet. I didn't get to review it properly and > I cannot say I would be too happy about using WQ from the page > allocator. I believe even the follow up needs to have WQ_RECLAIM WQ. > > [1] http://lkml.kernel.org/r/20170125083038.rzb5f43nptmk7aed@techsingularity.net Did you get chance to test with this follow up patch? It would be interesting to see whether OOM situation can still starve the waiter. The current linux-next should contain this patch. Thanks! -- 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