Sebastien.Roy <> wrote: > On Sun, 2009-09-06 at 13:39 +0800, Aubrey Li wrote: >> okay, thanks but need your another help. >> >> I did a quick investigation and found that there is a xorg related >> kthread causing >> the scheduler ping-pong between "idle" thread and this xorg related >> thread. >> >> Could you please disable X by "pfexec svcadm disable gdm" and try >> powertop again? >> Please make sure you are still using event mode, not poll-mode. > > With no Xorg, and with event mode, powertop indeed shows that the > system remains mostly in the lowest P-state.
Sounds good, it looks like we found the cause. Thanks for the validation! > I'm still a bit confused as to why poll and event modes would show > different results when Xorg is running... As I said, event mode is more aggressive. The load of Xorg is enough to drive p-state transition under event mode but it is ignored in the poll mode. > > Is there a CR filed against Xorg that I can look at? I wonder, is this a regression? With Xorg, did powertop report 100% highest p-state residency on b121 and previous version? If this is a regression, we need to ask Xorg guys what they did to hurt idle power, :) Thanks, -Aubrey
