Date: Thu, 01 Jan 2009 12:09:39 -0500 From: "Alexandre \"Sunny\" Kovalenko" <gaijin.k@gmail.com> To: Ian Smith <smithi@nimnet.asn.au> Cc: acpi <acpi@freebsd.org> Subject: Re: Problem on AMD64 Message-ID: <1230829779.1182.17.camel@RabbitsDen> In-Reply-To: <20081228124345.D51566@sola.nimnet.asn.au> References: <20081221233822.7E92545020@ptavv.es.net> <49500088.2080609@bigfoot.com> <7d6fde3d0812221315s4d03e15dw4b84679b98a6308f@mail.gmail.com> <49534F10.7040305@bigfoot.com> <7d6fde3d0812261912r1d5abd6cic1513f11cc59f1c5@mail.gmail.com> <20081227160941.I29108@sola.nimnet.asn.au> <1230388519.1270.1.camel@RabbitsDen> <20081228124345.D51566@sola.nimnet.asn.au>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sun, 2008-12-28 at 13:20 +1100, Ian Smith wrote: > On Sat, 27 Dec 2008, Alexandre "Sunny" Kovalenko wrote: > > On Sat, 2008-12-27 at 17:13 +1100, Ian Smith wrote: > > > On Fri, 26 Dec 2008, Garrett Cooper wrote: > > > > On Thu, Dec 25, 2008 at 1:14 AM, David van Kuijk <dynasore@bigfoot.com> wrote: > > > [..] > > > > >> Look into the following sysctls: > > > > >> > > > > >> hw.acpi.cpu.cx_lowest > > > > >> hw.acpi.cpu.cx_highest > > > > >> > > > > > > > > > > I tried to find out what I can do with those sysctls. > > > > > hw.acpi.cpu.cx_highest is not available on my system. > > > > > > I don't think it exists; C1 state is always available AFAIK. > > > > > > > > hw.acpi.cpu.cx_lowest is available and can be set. Are you suggesting I > > > > > should set it to C2 or C3??? > > > > > > Give it a try. Setting it to C3 won't hurt, whether it's used or not. > > > Actually it just might (hurt that is). See below for the discussion. > > > > http://www.freebsd.org/cgi/getmsg.cgi?fetch=0+2482 > > +/usr/local/www/db/text/2008/freebsd-acpi/20081109.freebsd-acpi > > Thanks. Yes that was indeed an interesting discussion. FWIW, I find > that interface awkward, without threading. For me it's easier from: > http://lists.freebsd.org/pipermail/freebsd-acpi/2008-November/005182.html > > Could I then safely say, setting it to C2 won't hurt? It is hard to generalize. I am using: RabbitsDen# sysctl dev.cpu.1.cx_lowest=C3 dev.cpu.1.cx_lowest: C2 -> C3 RabbitsDen# sysctl dev.cpu | grep cx dev.cpu.0.cx_supported: C1/1 C2/1 C3/57 dev.cpu.0.cx_lowest: C2 dev.cpu.0.cx_usage: 0.00% 100.00% 0.00% dev.cpu.1.cx_supported: C1/1 C2/1 C3/57 dev.cpu.1.cx_lowest: C3 dev.cpu.1.cx_usage: 0.00% 30.43% 69.56% without any obvious ill effects. Whether having C3 on one of the cores is makes any difference in power consumption or heat dissipation, I do not know. I also do not know whether there are machines out there which would exhibit odd behavior with C2 set. As usual, YMMV. -- Alexandre "Sunny" Kovalenko (Олександр Коваленко)
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?1230829779.1182.17.camel>