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

[drago01]

On Thu, May 31, 2012 at 8:04 PM, Josh Boyer <jwboyer at gmail.com> wrote:
> On Thu, May 31, 2012 at 1:02 PM, drago01 <drago01 at gmail.com> wrote:
>> On Wed, May 30, 2012 at 10:32 PM, Reindl Harald <h.reindl at thelounge.net> wrote:
>>>
>>>
>>> Am 30.05.2012 10:52, schrieb drago01:
>>>> On Wed, May 30, 2012 at 2:36 AM, Jared K. Smith
>>>> <jsmith at fedoraproject.org> wrote:
>>>>> On Tue, May 29, 2012 at 5:29 PM, Reindl Harald <h.reindl at thelounge.net> wrote:
>>>>>> Am 29.05.2012 22:45, schrieb Roberto Ragusa:
>>>>>> i think i have to mention taht VT-d is active in the BIOS and
>>>>>> i was wondering that it was stable because the combination of the
>>>>>> i915 options with VT-d (hardware supported virtualization IO) is
>>>>>> classified to be unstable
>>>>>
>>>>> Yes, that's a possible culprit. I've had massive problems with VT-d
>>>>> enabled on both a Thinkpad T510 and on a Thinkpad X220.  I don't
>>>>> pretend to understand what advantages VT-d is *supposed* to give me,
>>>>> but it's the first thing I turn off in the BIOS.  In fact, on the
>>>>> T510, I couldn't even get an installation to complete without turning
>>>>> it off.
>>>>
>>>> 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 ;)