Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754876Ab3H1Tec (ORCPT ); Wed, 28 Aug 2013 15:34:32 -0400 Received: from a10-51.smtp-out.amazonses.com ([54.240.10.51]:58369 "EHLO a10-51.smtp-out.amazonses.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754532Ab3H1Te2 (ORCPT ); Wed, 28 Aug 2013 15:34:28 -0400 X-Greylist: delayed 385 seconds by postgrey-1.27 at vger.kernel.org; Wed, 28 Aug 2013 15:34:28 EDT Date: Wed, 28 Aug 2013 19:28:02 +0000 From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Gilad Ben-Yossef cc: "Paul E. McKenney" , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Frederic Weisbecker Subject: Re: [PATCH v2 1/2] mm: make vmstat_update periodic run conditional In-Reply-To: Message-ID: <00000140c6659902-f76c4733-ff61-47d9-b0d2-69fd04253aa3-000000@email.amazonses.com> References: <1371672168-9869-1-git-send-email-gilad@benyossef.com> <0000013f61e7609b-a8d1907b-8169-4f77-ab83-a624a8d0ab4a-000000@email.amazonses.com> <000001405e70a92f-3b2a0b89-f807-45d7-af70-9e7292156dd4-000000@email.amazonses.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SES-Outgoing: 2013.08.28-54.240.10.51 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1231 Lines: 27 On Fri, 9 Aug 2013, Gilad Ben-Yossef wrote: > If the code does not consider setting the vmstat_cpus bit in the mask > unless we are running > on a CPU in tickless state, than we will (almost) never set > vmstat_cpus since we will (almost) > never be tickless in a deferrable work - Sorry never got around to answering this one. Not sure what to do about it. How about this: Disable the vmstats when there is no diff to handle instead? This means that the OS was quiet during the earlier period. That way you have an independent criteria for switching vmstat work off from tickless. Would even work when there are multiple processes running on the processor if none of them causes counter updates. In the meantime there are additional patches for the vmstat function pending for merge from me (not related to the conditional running of vmstat but may make it easier to implement). So if you want to do any work then please on top of the newer release available from Andrew's tree. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/