Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756251AbdGLMOO (ORCPT ); Wed, 12 Jul 2017 08:14:14 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:53848 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751215AbdGLMOM (ORCPT ); Wed, 12 Jul 2017 08:14:12 -0400 Date: Wed, 12 Jul 2017 14:14:06 +0200 From: Peter Zijlstra To: "Li, Aubrey" Cc: Frederic Weisbecker , Christoph Lameter , Andi Kleen , Aubrey Li , tglx@linutronix.de, len.brown@intel.com, rjw@rjwysocki.net, tim.c.chen@linux.intel.com, arjan@linux.intel.com, paulmck@linux.vnet.ibm.com, yang.zhang.wz@gmail.com, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v1 00/11] Create fast idle path for short idle periods Message-ID: <20170712121406.ugz7wvzz7lrgohqo@hirez.programming.kicks-ass.net> References: <1499650721-5928-1-git-send-email-aubrey.li@intel.com> <20170710084647.zs6wkl3fumszd33g@hirez.programming.kicks-ass.net> <20170710144609.GD31832@tassilo.jf.intel.com> <20170710164206.5aon5kelbisxqyxq@hirez.programming.kicks-ass.net> <20170710172705.GA3441@tassilo.jf.intel.com> <20170711094157.5xcwkloxnjehieqv@hirez.programming.kicks-ass.net> <20170711160926.GA18805@lerouge> <20170711163422.etydkhhtgfthpfi5@hirez.programming.kicks-ass.net> <496d4921-5768-cd1e-654b-38630b7d2e13@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <496d4921-5768-cd1e-654b-38630b7d2e13@linux.intel.com> User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 603 Lines: 14 On Wed, Jul 12, 2017 at 12:15:08PM +0800, Li, Aubrey wrote: > While my proposal is trying to leverage the prediction functionality > of the existing idle menu governor, which works very well for a long > time. Oh, so you've missed the emails where people say its shit? ;-) Look for the emails of Daniel Lezcano who has been working on better estimating the IRQ periodicity. Some of that has recently been merged but it hasn't got any users yet afaik. But as said before, I'm not convinced the actual idle time is the right measure for NOHZ, because many interrupts do not in fact re-enable the tick.