From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751879AbbASE1R (ORCPT ); Sun, 18 Jan 2015 23:27:17 -0500 Received: from smtp.codeaurora.org ([198.145.11.231]:36570 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751819AbbASE1Q (ORCPT ); Sun, 18 Jan 2015 23:27:16 -0500 Message-ID: <54BC879C.90505@codeaurora.org> Date: Mon, 19 Jan 2015 09:57:08 +0530 From: Vinayak Menon User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130329 Thunderbird/17.0.5 MIME-Version: 1.0 To: Christoph Lameter CC: Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, hannes@cmpxchg.org, vdavydov@parallels.com, mgorman@suse.de, minchan@kernel.org Subject: Re: [PATCH v2] mm: vmscan: fix the page state calculation in too_many_isolated References: <1421235419-30736-1-git-send-email-vinmenon@codeaurora.org> <20150114165036.GI4706@dhcp22.suse.cz> <54B7F7C4.2070105@codeaurora.org> <20150116154922.GB4650@dhcp22.suse.cz> <54BA7D3A.40100@codeaurora.org> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/18/2015 01:18 AM, Christoph Lameter wrote: > On Sat, 17 Jan 2015, Vinayak Menon wrote: > >> which had not updated the vmstat_diff. This CPU was in idle for around 30 >> secs. When I looked at the tvec base for this CPU, the timer associated with >> vmstat_update had its expiry time less than current jiffies. This timer had >> its deferrable flag set, and was tied to the next non-deferrable timer in the > > We can remove the deferrrable flag now since the vmstat threads are only > activated as necessary with the recent changes. Looks like this could fix > your issue? > Yes, this should fix my issue. But I think we may need the fix in too_many_isolated, since there can still be a delay of few seconds (HZ by default and even more because of reasons pointed out by Michal) which will result in reclaimers unnecessarily entering congestion_wait. No ? -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation