[ubuntu-x] Hybrid graphics detection

[Bryce Harrington]

On Wed, Nov 02, 2011 at 06:00:18PM -0400, Evan Broder wrote:
> To briefly summarize the session, we felt that we couldn't present any
> "true" hybrid graphics support (any sort of GPU switching, dynamic or
> otherwise) to non-power users within the scope of Precise, so we
> wanted to focus on not making it possible to use your hardware at all
> under the standard configuration.
> 
> The issue I'm concerned about is that with most hybrid graphics
> hardware configurations, the OS sees multiple GPUs, and most of the
> tools assume there will only be one.
> 
> For example, if you have nVidia Optimus, Jockey sees an nVidia GPU,
> and installs the nvidia-current driver. That changes your default
> libGL. When you reboot, and the Intel GPU is connected to the outputs,
> the nVidia libGL doesn't work with the Intel driver.

Finally we got our hands on one of these systems, and already it's
fixed, and even SRU'd to oneiric:  #885204

If anyone is on oneiric and has this hardware, you can help by
enabling oneiric-proposed, uninstall nvidia, update to the fixed jockey,
verify it no longer recommends nvidia, and comment either way on the bug
report.

https://bugs.launchpad.net/ubuntu/+source/jockey/+bug/885204

> > As you understand I am not an expert on the issue, just recently got
> > my hands on some of these hybrid GPU laptops. To me the biggest
> > problem, and one that actually makes Linux unusable for many users
> > (those who know even less than me and actually use it on the go), is
> > that the unused card is running full power.
> 
> 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.

> > And you, our last hope, have *one* system to test on? Can't some
> > corporate goodness throw a handful of lappies at you?

It's astounding how effective just having the hardware on hand is.  The
two systems we've been looking at this week will be going with Chris,
and the certification team says they'll send me another (which is
failing some cert tests).

We've got other higher priority projects this cycle, but we do hope to
at least knock down some of the main hybrid graphics bugs (like the two
mentioned above) that are preventing people from using their systems as
ordinary laptops.  Beyond that, well time will tell.

Bryce