[ltp] Re: T410 does not have a power state below C3

Pedro Ribeiro linux-thinkpad@linux-thinkpad.org
Sun, 19 Dec 2010 21:53:11 +0000

On 19 December 2010 20:31, Henrique de Moraes Holschuh <hmh@hmh.eng.br> wro=
> On Wed, 15 Dec 2010, Pedro Ribeiro wrote:
>> Sorry for the insistence, but this is severely impacting my battery
>> life, as well as creating a lot of heat.
>> Does anyone here with a T410 have the same problem?
>> Henrique, what's your take on this?
> Try using a new kernel, with the intel-idle driver (instead of
> acpi-idle). =A0Don't bother with whichever C-state it will list, it is
> probably false with that driver but it should try the best possible
> idling. =A0Might hang Lenovo's BIOS, so do a first-time careful test (e.g=
> boot read-only and wait a bit to see if it will hang).
> Other than that, I don't know. =A0Try unloading uhci-hcd and ehci-hcd,
> etc. =A0See if intel's new version of powertop is available anywhere, and
> try it, etc.
> If nothing else works, bring in the large guns. =A0Compile a perf kernel
> and look in the web about instructions on how to use the perf tool, then
> use it to find out WTF is keeping the system up all the time.
> --
> =A0"One disk to rule them all, One disk to find them. One disk to bring
> =A0them all and in the darkness grind them. In the Land of Redmond
> =A0where the shadows lie." -- The Silicon Valley Tarot
> =A0Henrique Holschuh

Thanks for your reply.

I think that I'm actually hitting state C6 after all, powertop just
doesn't report it.
I've downloaded a tool called i7z which is made specifically for iX
cores and it does report I'm hitting state C6.