On Mon, 2008-06-30 at 09:10 +0200, Adam Tkac wrote:
On Fri, Jun 27, 2008 at 05:13:24PM +0100, Richard Hughes wrote:
> * remove CONFIG_CPU_FREQ_GOV_POWERSAVE -- ondemand automatically
> throttles down to lowest, and is just a hardcoded state
I don't think removal of powersave governor is good idea. Generally
ondemand governor does great job but in some cases doesn't. For
example when I play some films in mplayer ondemand sets frequency to
max which is not needed, of course.
Right, so we need to fix ondemand to be cleverer.
Powersave governor is also good in case that you have bad fan in
laptop and you are going to compile some big source. Without powersave
it is not possible (yes, it really happens :) )
Right, thermal management is similar to power management for the action
but not for the policy. I don't think forcing the lowest speed setting
is the correct way to fix this. If the laptop is running cool, why use
the slowest speed?
> Matthew Garrett and I are working on a latency profile for
> management, and having all these modules potentially loaded is bad.
I think we should preserve ondemand and powersave governors (and
potentialy others as Dave Jones wrote in this thread). Please don't
drop them in favour of your project which might be generally better but
I believe there are cases where current governors are better.
Right, cheers for your feedback. In view of everybodies comments, what
about the following:
* Compile _into_ the kernel ondemand, performance, powersave and
* Default to performance in the kernel rather than userspace
* Build as a module conservative with the view of just fixing ondemand
if there are any special use-cases that conservative is better at
* Export the P and C state latency to userspace and let the system
policy dictate the governor. For instance, even for machines that have a
long latency for changing P states should be able to use ondemand if we
want to save maximum power.
How does that sound?