[Intel-gfx] Very bad performance from intel chipset on Thinkpad T540p (2880x1620)

[Chris Wilson]

On Fri, Apr 24, 2015 at 08:35:33AM -0700, Marc MERLIN wrote:
> On Fri, Apr 24, 2015 at 07:53:29AM +0100, Chris Wilson wrote:
> > > On top of being bleeding edge enoug not to be in debian unstable, does it have 
> > > performance enhancements that you are hopeful will help my situation?
> > 
> > Lots.
> 
> :)
> 
> Ok, so I owe you thanks.
> 
> Between the module options and the new driver, things are better.
> I can now play and resize a video with mplayer without it dropping to 5fps
> or less. I see some tearing in the video being played on occasion whether
> it's original size, resized window, or full screen, but otherwise it plays
> full speed and my system doesn't slow down to a crawl.

(In the absence of driver bugs...)

Whether of not it tears depends upon your window manager. On bare X,
using mplayer -vo xv or -vo gl, should not tear. Under a compositing
window manager, it depends upon how it decides to update the screen. To
force everything to update without tearing, use

echo > /etc/X11/xorg.conf.d/90-intel.conf <<EOF
Section "Device"
	Identifier "igfx"
	Option "TearFree"
EndSection
EOF
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre