F16: Sandy Bridge -> lags, missing effects, ui-crashes

[Josh Boyer]

On Thu, May 31, 2012 at 2:45 PM, drago01 <drago01 at gmail.com> wrote:
> On Thu, May 31, 2012 at 8:04 PM, Josh Boyer <jwboyer at gmail.com> wrote:
>>>>> You could just do boot with intel_iommu=igfx_off to verify that
>>>>
>>>> sounds not really smart if you are using the integrated graphics
>>>> engine as only graphics card which is fast enough for KDE4 3D
>>>> effects and all the things you need if you are not a gamer :-)
>>>
>>> You misunderstood this completely this won't "turn off your GPU" but
>>> just disables DMAR for it ...
>>> You shouldn't notice any difference neither in KDE nor in games.
>>
>> You're aware that doesn't actually do anything in Fedora kernels,
>> right?  We've been carrying a patch called
>> linux-2.6-intel-iommu-igfx.patch for quite some time that removes the
>> igfx_off variable and replaces it with an igfx_on variable and defaults
>> to having the DMAR disabled without igfx_on being specified.  In fact:
>>
>> From: drago01 <drago01 at gmail.com>
>> Date: Wed, 26 Oct 2011 13:37:27 -0400
>> Subject: [PATCH] Default to igfx_off
>
> Oops ... has been a while ;)

Good reminder though.  Now that I've said we carry that, we discussed
it in the #fedora-kernel channel and we're going to drop it in rawhide.
So, in the future that option will indeed be viable but hopefully Intel
fixes up i915 so it's not needed.

josh