Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
Power Management Configuration for Core 2 Duo E4500
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware
View previous topic :: View next topic  
Author Message
SlackwareInAZ
Tux's lil' helper
Tux's lil' helper


Joined: 29 Aug 2005
Posts: 92

PostPosted: Fri Feb 01, 2008 5:16 pm    Post subject: Power Management Configuration for Core 2 Duo E4500 Reply with quote

Recently built a new computer with Core 2 Duo E4500 processors.

Other than the obvious reconfiguring the kernel for the switch from Pentium4 to Core 2 Duo I have not changed anything else in the kernel configuration.

I never enabled power management for the previous kernel and I wanted a few tips or a link explaining the new options in the 2.6.24 kernel power management section.

In Windows Vista the processors step down at idle to 1100mhz. Full speed is 2200mhz.

I know somewhere in /proc it lists processor speed.

I saw the on demand and full speed options in the .config file. I want the processor management to mimic how Vista does it, if not better.

And should these options be compiled into the kernel or as modules? I would prefer the module option if it is effective.

Thanks for any information.

Gary :)
Back to top
View user's profile Send private message
Dottout
l33t
l33t


Joined: 07 Mar 2006
Posts: 882

PostPosted: Fri Feb 01, 2008 5:34 pm    Post subject: Reply with quote

enable acpi and cpu frequency scaling support in kernel config, ondemand governor is what you need. and yes, you can build it as module
Back to top
View user's profile Send private message
SlackwareInAZ
Tux's lil' helper
Tux's lil' helper


Joined: 29 Aug 2005
Posts: 92

PostPosted: Fri Feb 01, 2008 6:03 pm    Post subject: Reply with quote

Thanks Dottout.

Just found this informative link: http://gentoo-wiki.com/HARDWARE_Intel_Core2_Duo

Emerged cpufreq-utils and just compiled a kernel with power management enabled. Played it safe and compiled everything into the kernel. Will probably recompile with modules now.

Take care,
Gary :D
Back to top
View user's profile Send private message
Paapaa
l33t
l33t


Joined: 14 Aug 2005
Posts: 955
Location: Finland

PostPosted: Fri Feb 01, 2008 7:03 pm    Post subject: Re: Power Management Configuration for Core 2 Duo E4500 Reply with quote

SlackwareInAZ wrote:
I saw the on demand and full speed options in the .config file. I want the processor management to mimic how Vista does it, if not better.


Use ondemand governor. Kernel 2.6.24 let's you select ondemand as the default governor so you don't need cpufreq-utils at all. It Just Works (tm).

SlackwareInAZ wrote:
And should these options be compiled into the kernel or as modules? I would prefer the module option if it is effective.


Build everything you always need straight in kernel. There is no reason not to.
_________________
Paludis, the way packages are meant to be managed.
Back to top
View user's profile Send private message
SlackwareInAZ
Tux's lil' helper
Tux's lil' helper


Joined: 29 Aug 2005
Posts: 92

PostPosted: Sat Feb 02, 2008 4:15 am    Post subject: Reply with quote

Paapaa, thanks for the info.

New update: found that compiling into the kernel does work better than modules. I think I like conservative governor better as cpufreq says my 2200mhz cores have three steps, 1.2, 1.6 and 2.2 Ghz. On demand seems to only give 1.2 or 2.2, but with the conservative governor I sometimes see 1.6 Ghz.

But new problem-- due to an unrelated xorg-server problem I decided to redo the kernel (third time today). The problem is if I use my old .config file which I've used at least since 2.6.20 or 2.6.21 kernels I have an entry for ACPI in power management. This must be checked for the ACPI Processor P-states driver (needed for Core 2 Duo processors) to be visible under the CPU Frequency scaling section.

Starting menuconfig without any .config file ACPI Support is not visible under Power Management. What do I need to enable to make ACPI Support reappear? I know that I should be able to regenerate any values that 2.6.24 kernel supports, so what's up with this??!!

F.Y.I. -- For testing purposes, I downloaded 2.6.23 and did menuconfig without an existing .config file. As long as Power Management menu item is selected, ACPI Support is present, but not in 2.6.24. So the question is has ACPI support been removed for 2.6.24? I think I must have to check some processor option to enable it, but I can't find it. I hate to have to use my old .config file.

Any info would be greatly appreciated for this bizarre problem.

Thanks,
Gary :(
Back to top
View user's profile Send private message
SlackwareInAZ
Tux's lil' helper
Tux's lil' helper


Joined: 29 Aug 2005
Posts: 92

PostPosted: Sat Feb 02, 2008 4:32 am    Post subject: Reply with quote

Found it! PCI Support needs to be enabled. Used the search feature for ACPI and noticed PCI Support under the list.

Although I learn a lot when starting from a blank .config file, I wish there was an easier way to see what else might be missing. If you don't configure one option, such as Configure standard kernel features (for small systems) under General Setup, you won't get the Memory Split entry under Processor types and features.

Wonder if a different configuring method would eliminate this? :?

Gary
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum