Date: Tue, 06 Jan 2015 16:41:06 -0500 From: Jung-uk Kim <jkim@FreeBSD.org> To: Kevin Oberman <rkoberman@gmail.com>, Sean Bruno <sbruno@freebsd.org> Cc: freebsd-acpi <freebsd-acpi@freebsd.org>, Nathan Whitehorn <nwhitehorn@freebsd.org> Subject: Re: Haswell, i3, fail to acpi_throttle fail Message-ID: <54AC5672.4060503@FreeBSD.org> In-Reply-To: <CAN6yY1vnSLi7%2B0beSSC5awJtZ%2Bt4iWBOcery8Z%2Bt=Wki9LyJBg@mail.gmail.com> References: <54AB32AD.1070409@ignoranthack.me> <CAN6yY1vnSLi7%2B0beSSC5awJtZ%2Bt4iWBOcery8Z%2Bt=Wki9LyJBg@mail.gmail.com>
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On 01/05/2015 22:57, Kevin Oberman wrote: > On Mon, Jan 5, 2015 at 4:56 PM, Sean Bruno > <sbruno@ignoranthack.me> wrote: > >> >> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 >> >> acpi_throttle0: <ACPI CPU Throttling> on cpu0 acpi_throttle0: >> P_CNT from P_BLK 0x1810 est0: <Enhanced SpeedStep Frequency >> Control> on cpu0 acpi_throttle1: <ACPI CPU Throttling> on cpu1 >> acpi_throttle1: failed to attach P_CNT device_attach: >> acpi_throttle1 attach returned 6 est1: <Enhanced SpeedStep >> Frequency Control> on cpu1 acpi_throttle2: <ACPI CPU Throttling> >> on cpu2 acpi_throttle2: failed to attach P_CNT device_attach: >> acpi_throttle2 attach returned 6 est2: <Enhanced SpeedStep >> Frequency Control> on cpu2 acpi_throttle3: <ACPI CPU Throttling> >> on cpu3 acpi_throttle3: failed to attach P_CNT device_attach: >> acpi_throttle3 attach returned 6 est3: <Enhanced SpeedStep >> 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 management, it has long since been superseded by TCC.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
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