On Thu, Nov 03, 2011 at 11:44:14AM -0400, Christopher James Halse Rogers wrote: > On Thu, 2011-11-03 at 06:52 -0700, Bryce Harrington wrote: > > On Thu, Nov 03, 2011 at 09:29:02AM -0400, Christopher James Halse Rogers > > wrote: > > > > > > > > > > However, we talked about powering off the discrete card as well. My > > > > > recollection is that the X team was planning to look into that, but > > > > > there are unknowns about how and when we can do that. > > > > > > > > Chris was given a system that exhibits this problem, so we've had a > > > > chance to review it as well. We've spoken to the kernel team about the > > > > issue and I think a fix should be forthcoming down the pike. Chris can > > > > fill in mroe. > > > > > > Simply writing "OFF" to /sys/kernel/debug/vgaswitcheroo/switch will turn > > > off the unconnected GPU on the system I've been playing with - and cuts > > > idle power consumption by > 50%. > > > > > > For this particular system this is entirely safe - the radeon card isn't > > > hooked up to any outputs at all, so if the radeon driver is loaded then > > > the radeon card is useless. The switcheroo interface only exists when > > > radeon is loaded, so unconditionally writing "OFF" to it *on this > > > system* is the right thing to do. > > > > Would it make sense to make that into a udev rule? > > I'm not sure that a udev rule would have the necessary context, but > either a udev rule or an upstart script would absolutely make sense.
Would any context be needed beyond loaded kernel gfx driver(s) and machine identification info? Bryce -- Ubuntu-x mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-x
