Messages in this thread | | | From | "Rafael J. Wysocki" <> | Subject | Re: Performance issue since 3.2.6 | Date | Tue, 22 Jan 2013 00:09:41 +0100 |
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On Monday, January 21, 2013 11:57:06 PM Olivier Doucet wrote: > Good evening, > > >> I'll try to track this commit. > > > > Thanks a lot! > > I failed to find a working version today with CONFIG_PM=y > (tested 3.2.6, 3.2.5, 3.2.0, 3.0.1, 2.6.32.8). I'll try older kernels tomorrow.
I don't think that's necessary. It looks like CONFIG_PM=y has never really worked for you, but you wasn't aware of that.
> I'm very sceptical now : how can a bug with such a big impact (25% > performance drop) can survive for so many years, with no one seeing it > ? > Good point is that benchmark can be easily done (it took less than an > hour to test a new version). If you have patches to be tested, feel > free to ask :) > > In the meanwhile, do you think I can compile a working 3.7 kernel ? > Maybe by activating / deactivating specific options ?
I'm really not sure. It looks like CONFIG_PM makes PM QoS affect cpuidle for you in a wrong way, so to speak.
I suppose it's time to look into the code and see what makes the difference.
Thanks, Rafael
-- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center.
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