From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753066AbbAVQLh (ORCPT ); Thu, 22 Jan 2015 11:11:37 -0500 Received: from resqmta-po-09v.sys.comcast.net ([96.114.154.168]:44376 "EHLO resqmta-po-09v.sys.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752545AbbAVQLe (ORCPT ); Thu, 22 Jan 2015 11:11:34 -0500 Date: Thu, 22 Jan 2015 10:11:31 -0600 (CST) From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Michal Hocko cc: Vinayak Menon , 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 In-Reply-To: <20150121143920.GD23700@dhcp22.suse.cz> Message-ID: 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> <54BC879C.90505@codeaurora.org> <20150121143920.GD23700@dhcp22.suse.cz> Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 21 Jan 2015, Michal Hocko wrote: > I think we can solve this as well. We can stick vmstat_shepherd into a > kernel thread with a loop with the configured timeout and then create a > mask of CPUs which need the update and run vmstat_update from > IPI context (smp_call_function_many). Please do not run the vmstat_updates concurrently. They update shared cachelines and therefore can cause bouncing cachelines if run concurrently on multiple cpus.