From owner-freebsd-acpi@FreeBSD.ORG  Wed Oct  3 16:24:12 2012
Return-Path: <owner-freebsd-acpi@FreeBSD.ORG>
Delivered-To: freebsd-acpi@FreeBSD.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id AF30D106566B;
	Wed,  3 Oct 2012 16:24:12 +0000 (UTC) (envelope-from avg@FreeBSD.org)
Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140])
	by mx1.freebsd.org (Postfix) with ESMTP id CC89A8FC15;
	Wed,  3 Oct 2012 16:24:11 +0000 (UTC)
Received: from odyssey.starpoint.kiev.ua (alpha-e.starpoint.kiev.ua
	[212.40.38.101])
	by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id TAA07996;
	Wed, 03 Oct 2012 19:24:07 +0300 (EEST)
	(envelope-from avg@FreeBSD.org)
Message-ID: <506C66A6.4070003@FreeBSD.org>
Date: Wed, 03 Oct 2012 19:24:06 +0300
From: Andriy Gapon <avg@FreeBSD.org>
User-Agent: Mozilla/5.0 (X11; FreeBSD amd64;
	rv:15.0) Gecko/20120911 Thunderbird/15.0.1
MIME-Version: 1.0
To: Sean Bruno <seanbru@yahoo-inc.com>
References: <504EDBEB.6010104@FreeBSD.org>
	<1349198313.4246.3.camel@powernoodle.corp.yahoo.com>
	<506C38CE.4090400@FreeBSD.org>
	<1349281266.13749.0.camel@powernoodle.corp.yahoo.com>
In-Reply-To: <1349281266.13749.0.camel@powernoodle.corp.yahoo.com>
X-Enigmail-Version: 1.4.3
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Cc: "sbruno@FreeBSD.org" <sbruno@FreeBSD.org>,
	"freebsd-acpi@freebsd.org" <freebsd-acpi@FreeBSD.org>
Subject: Re: notify userland about C-state changes
X-BeenThere: freebsd-acpi@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: ACPI and power management development <freebsd-acpi.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-acpi>,
	<mailto:freebsd-acpi-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-acpi>
List-Post: <mailto:freebsd-acpi@freebsd.org>
List-Help: <mailto:freebsd-acpi-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-acpi>,
	<mailto:freebsd-acpi-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 03 Oct 2012 16:24:12 -0000

on 03/10/2012 19:21 Sean Bruno said the following:
> On Wed, 2012-10-03 at 06:08 -0700, Andriy Gapon wrote:
>>>
>>> So quick question, does this happen a lot on a system with a
>> sporadic
>>> workload?  Does this introduce overhead to the system to service the
>>> notification requests?
>>
>> I am not sure who can answer this question.  It is up to ACPI platform
>> to decide
>> when it changes _available C-states_.  OS doesn't have control over
>> that.
>>
> Hrm ... what changes to the machine would make this happen while the
> machine is running?  things like the switching from battery to line
> power?

Yes.  Or something else [?] of similar nature/effect.

>> P.S.  I hope you haven't confused this notification for a notification
>> about
>> _current_ C-state changing. 
> 
> I did have it confused.  Thanks for putting this note in.

OK :-)

-- 
Andriy Gapon