Intel Pineview & screen rotation = S L O W

[Florian Echtler]

Hello again,

I've since upgraded to Ubuntu 10.04 and the problem persists: rotating
the screen really bogs the system down.

(Probably) relevant packages are:
xserver-xorg-core 1.7.6
xserver-xorg-video-intel 2.9.1

Some excerpts from Xorg.0.log:

(==) intel(0): Depth 24, (--) framebuffer bpp 32
(==) intel(0): RGB weight 888
(==) intel(0): Default visual is TrueColor
(II) intel(0): Integrated Graphics Chipset: Intel(R) Pineview GM
(--) intel(0): Chipset: "Pineview GM"

[...]

(II) intel(0): [DRI2] Setup complete
(**) intel(0): Framebuffer compression disabled
(**) intel(0): Tiling enabled
(**) intel(0): SwapBuffers wait enabled
(==) intel(0): VideoRam: 262144 KB
(II) intel(0): Attempting memory allocation with tiled buffers.
(II) intel(0): Tiled allocation successful.
(II) UXA(0): Driver registered support for the following operations:
(II)         solid
(II)         copy
(II)         composite (RENDER acceleration)
(==) intel(0): Backing store disabled
(==) intel(0): Silken mouse enabled
(II) intel(0): Initializing HW Cursor
(II) intel(0): No memory allocations
(II) intel(0): RandR 1.2 enabled, ignore the following RandR disabled
message.
(==) intel(0): DPMS enabled
(==) intel(0): Intel XvMC decoder disabled
(II) intel(0): Set up textured video
(II) intel(0): Set up overlay video
(II) intel(0): direct rendering: DRI2 Enabled
(--) RandR disabled

Is there any tweak I could attempt, or is a rotated screen simply
supposed to be slow?

> I've got a new netbook with an Intel Atom N450 and a Pineview integrated
> GFX controller. I'm running Ubuntu 9.10 with Xorg 1.6.4. As it's a
> tablet/convertible, I'd like to be able to switch the screen orientation
> from time to time. This does work find with xrandr, however, any
> rotation except "normal" (i.e., "left","right", and "inverted") is very
> slow (e.g, Firefox is barely usable anymore). An entirely non-scientific
> test with glxgears gives a framerate of 1190 FPS in normal mode and
> around 250 in any rotated mode.
> Is this to be expected, or is there a glitch somewhere?

Florian