Thanks for the pointers Viresh. I gave a quick look into ftrace. Surely it will be helpful for my analysis as it has info on time taken by each function. Hope further analysis using ftrace can give me more pointers. Cheers, karthik On Tue, Sep 17, 2013 at 1:01 AM, Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote: > On 17 September 2013 07:43, karthik vm <meetvm@xxxxxxxxx> wrote: >> Yeah actually that is what my concern is. It seems that for changing >> the frequency we need to acquire a lock (in cpufreq_driver_target()). >> Hence even though the hardware is capable of ns level DVFS, OS >> overhead may be large enough to take advantage of it. Can we measure >> this overhead? > > There are a lot of other things that we really need to look before this > one.. > > The way we are changing frequency currently is very delayed... There > are few other threads that are going around power aware scheduler > which you might be interested in.. Look for them in Archives.. > > Coming back to your question, these kind of overheads will always be > there, isn't it? Normally that lock will be acquired fairly quickly as there > might be no contention.. > > Yeah, you can measure it but don't know who is your best friend in > term of tools.. Maybe ftrace can get you some details. -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
