From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751453AbcAZSpq (ORCPT ); Tue, 26 Jan 2016 13:45:46 -0500 Received: from mail-wm0-f53.google.com ([74.125.82.53]:37327 "EHLO mail-wm0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751230AbcAZSpm (ORCPT ); Tue, 26 Jan 2016 13:45:42 -0500 Message-ID: <1453833939.3534.68.camel@gmail.com> Subject: Re: fast path cycle muncher (vmstat: make vmstat_updater deferrable again and shut down on idle) From: Mike Galbraith To: Christoph Lameter Cc: Michal Hocko , Peter Zijlstra , LKML Date: Tue, 26 Jan 2016 19:45:39 +0100 In-Reply-To: References: <20160121165148.GF29520@dhcp22.suse.cz> <20160122140418.GB19465@dhcp22.suse.cz> <20160122161201.GC19465@dhcp22.suse.cz> <1453566115.3529.8.camel@gmail.com> <20160125174224.GH23934@dhcp22.suse.cz> <20160125201319.GA19020@dhcp22.suse.cz> <1453833078.3534.59.camel@gmail.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.16.5 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2016-01-26 at 12:34 -0600, Christoph Lameter wrote: > On Tue, 26 Jan 2016, Mike Galbraith wrote: > > > I disagree. You're burning electrons for no benefit at all to me on my > > box. You want to do high speed trading, that's fine, but I expect my > > box to be able to pop in and out of idle without having to pay a toll > > to the high speed trading bandits of the world, thank you very much. > > > > This specialty thing does not belong in the generic fast path. > > The system going idle is a fastpath. Mind boogling. Hohum, noted. Now what about those cycles, and the sleeping lock you injected for -rt? -Mike