On Tuesday, August 03, 2010, Paul E. McKenney wrote: > On Mon, Aug 02, 2010 at 11:33:32PM +0200, Rafael J. Wysocki wrote: > > On Monday, August 02, 2010, Paul E. McKenney wrote: > > > On Mon, Aug 02, 2010 at 03:52:20PM +0200, Rafael J. Wysocki wrote: > > > > On Monday, August 02, 2010, Paul E. McKenney wrote: > > > > > On Sun, Aug 01, 2010 at 03:47:08PM -0700, Arjan van de Ven wrote: > > > > > > On Sun, 1 Aug 2010 12:12:28 -0700 > > > > > > "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> wrote: > > > > ... > > > > > > Another one: freezing whole cgroups..... we have that today. it > > > > > > actually works quite well.... of course the hard part is the decision > > > > > > what to put in which cgroup, and at what frequency and duration you let > > > > > > cgroups run. > > > > > > > > > > Indeed, the Android guys seemed to be quite excited by cgroup freezing > > > > > until they thought about the application-classification problem. > > > > > Seems like it should be easy for some types of applications, but I do > > > > > admit that apps can have non-trivial and non-obvious dependencies. > > > > > > > > This isn't more difficult than deciding which applications will be allowed to > > > > use wakelocks (in the wakelocks world). It actually seems to be pretty much > > > > equivalent to me. :-) > > > > > > If I understand correctly, the problem they were concerned about was > > > instead "given that a certain set of apps are permitted to use wakelocks, > > > which of the other apps can safely be frozen when the display blanks > > > itself." > > > > I _think_ the problem should be reformulated as "which of the other apps > > can be safely frozen without causing the wakelocks-using ones to have > > problems" instead (the particular scenario is that one of the wakelocks-using > > apps may need one of the other apps to process something and therefore the > > other app cannot be frozen; however, that may be resolved by thawing all of > > the other apps in such situations IMO). > > I agree that your statement is equivalent to mine. From what I can see, > the current Android code resolves this by not freezing any app while > a wakelock is held. > > Just out of curiosity, how are you detecting the situation in order to > decide when to thaw the apps in the cgroup? Well, in fact I would only be able to talk about that theoretically, as I'm currently not involved in any project using cgroups for power management. I have considered that, but I haven't tried to implement it. Thanks, Rafael _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
