From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757746AbdJQAKy (ORCPT ); Mon, 16 Oct 2017 20:10:54 -0400 Received: from cloudserver094114.home.net.pl ([79.96.170.134]:52511 "EHLO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753432AbdJQAKx (ORCPT ); Mon, 16 Oct 2017 20:10:53 -0400 From: "Rafael J. Wysocki" To: "Li, Aubrey" Cc: Aubrey Li , tglx@linutronix.de, peterz@infradead.org, len.brown@intel.com, ak@linux.intel.com, tim.c.chen@linux.intel.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v2 6/8] cpuidle: make fast idle threshold tunable Date: Tue, 17 Oct 2017 02:01:17 +0200 Message-ID: <6153229.9lQq4PJGJ7@aspire.rjw.lan> In-Reply-To: References: <1506756034-6340-1-git-send-email-aubrey.li@intel.com> <2242303.t20yq9Lc6j@aspire.rjw.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit 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 Monday, October 16, 2017 8:00:45 AM CEST Li, Aubrey wrote: > On 2017/10/14 8:59, Rafael J. Wysocki wrote: > > On Saturday, September 30, 2017 9:20:32 AM CEST Aubrey Li wrote: > >> Add a knob to make fast idle threshold tunable > >> > >> Signed-off-by: Aubrey Li > > > > I first of all am not sure about the need to add a tunable for this at all > > in the first place. > > Actually I think a fixed value(10) might be good enough but not quite sure > if there is a requirement to tune it for different scenario, for example even > if the predicted idle interval is 100x overhead, I still want a fast path for > a better benchmark score? Any new tunables make the test matrix expand considerably, so it generally is better to err on the conservative side with adding them. Thanks, Rafael