From owner-freebsd-acpi@FreeBSD.ORG Tue Jan 6 21:41:07 2015 Return-Path: Delivered-To: freebsd-acpi@freebsd.org Received: from mx2.freebsd.org (mx2.freebsd.org [IPv6:2001:1900:2254:206a::19:2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id AE902A2C; Tue, 6 Jan 2015 21:41:07 +0000 (UTC) Received: from hammer.pct.niksun.com (freefall.freebsd.org [IPv6:2001:1900:2254:206c::16:87]) by mx2.freebsd.org (Postfix) with ESMTP id 4D2FE2CFC; Tue, 6 Jan 2015 21:41:07 +0000 (UTC) Message-ID: <54AC5672.4060503@FreeBSD.org> Date: Tue, 06 Jan 2015 16:41:06 -0500 From: Jung-uk Kim User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: Kevin Oberman , Sean Bruno Subject: Re: Haswell, i3, fail to acpi_throttle fail References: <54AB32AD.1070409@ignoranthack.me> In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Cc: freebsd-acpi , Nathan Whitehorn X-BeenThere: freebsd-acpi@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: ACPI and power management development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 06 Jan 2015 21:41:07 -0000 On 01/05/2015 22:57, Kevin Oberman wrote: > On Mon, Jan 5, 2015 at 4:56 PM, Sean Bruno > wrote: > >> >> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 >> >> acpi_throttle0: on cpu0 acpi_throttle0: >> P_CNT from P_BLK 0x1810 est0: > Control> on cpu0 acpi_throttle1: on cpu1 >> acpi_throttle1: failed to attach P_CNT device_attach: >> acpi_throttle1 attach returned 6 est1: > Frequency Control> on cpu1 acpi_throttle2: >> on cpu2 acpi_throttle2: failed to attach P_CNT device_attach: >> acpi_throttle2 attach returned 6 est2: > Frequency Control> on cpu2 acpi_throttle3: >> on cpu3 acpi_throttle3: failed to attach P_CNT device_attach: >> acpi_throttle3 attach returned 6 est3: > Frequency Control> on cpu3 >> >> >> The call to acpi_bus_alloc_gas() in acpi_throttle.c seems to be >> failing to attach. What should I be poking at here? >> > > Excellent! Throttling is counter-productive and always has been. > It's been at least 5 years since mav@ posted his excellent wiki > article on power management which demonstrated the futility of > throttling. More important, even if it was useful for power > management, it has long since been superseded by TCC. Intel tried > to make the purpose of TCC clear by the name: Thermal Control > Circuit. So it is ineffective for power management and FreeBSD > still tries to use it. Looks like the vendor broke ACPI so > throttling won't work. Or, maybe, Intel simply removed it as > unused legacy. > > Don't worry. Be happy! Make sure that > hint.acpi_throttle.0.disabled=1 is set in /boot/loader.conf to > disable it. I'd strongly urge that you also disable P4TCC with > hint.p4tcc.0.disabled=1. It will trivially improve battery life > and will seriously compromise performance if powerd is enabled. It > can also cause hangs with elevated C-states on some systems. FYI, acpi_throttle and tcc have been disabled by default for a while. https://svnweb.freebsd.org/changeset/base/265329 I guess Nathan forgot to MFC this commit? Jung-uk Kim