Arch Linux

keratos

Member

Registered: 2008-04-27

Posts: 138

no problem more of a question on X11/intel and 2.26/i915 module

Installed arch linux this morning and performed a 'pacman -Sy && packman -Su'.

Now I'm running X using the intel video driver on my 965GM chip. Framerate is 890fps according to glxgears. No problems with 2D/3D nor video. The only entry in my xorg.conf file is:

Section "Device"
Identifier "Video"
Driver "intel"
AccelMethod "EXA"
EndSection

I had to put this in because without an xorg.conf file , X was crashing. I guess XAA buggy in most latest intel driver?

Upon reading about DRI2 and UXA I followed this: http://wiki.archlinux.org/index.php/Intel_Graphics , then tweaked my xorg.conf and the following observations were noted:

with UXA enabled fps=500
with XXA enabled (symbol error in intel_driver.so so X cashed)
with EXA enabled fps=600

In UXA and EXA cases there were NO errors or warnings in the X log file (other than some BIOS warnings which are always there even with my default install and the same warnings I have noted in other users' Xorg log)

If I restore to my default original install then fps=890.

So it appears that all combinations of DRI2/DRI and UXA/EXA are in fact SLOWER than the stock setup.

Can someone explain what is going on here please? Just for my information.

Many thanks.

Last edited by keratos (2009-04-30 08:20:47)

combuster

Member

From: Serbia

Registered: 2008-09-30

Posts: 711

Website

Re: no problem more of a question on X11/intel and 2.26/i915 module

Well the situation right now is as followes:

With GEM and UXA being mature it looks like the support for XAA and EXA are gonna be dropped sometime soon. Right now there are performance issues with the 2.6.29 kernel but when 2.6.30 hits the stable it is going to be much better. Right now 2.7.0 intel driver doesn't get allong well with 2.6.29 so we will have to wait for 2.6.30, untill then 2.6.29 and video-intel-2.6.3-3 with UXA is the best solution. I think that in next 1-3 months the things will get better for us and with 2.6.30 kernel and 2.7.0 driver we are going to experience many improvements. Last two years were a disaster for intel users, EXA, TTM, UXA, GEM, drivers going both ways, kernel quirks and the rest of the stuff made our 3d venture misserable... Developers are turning toward tweaking the code for UXA and GEM only...

keratos

Member

Registered: 2008-04-27

Posts: 138

Re: no problem more of a question on X11/intel and 2.26/i915 module

Thanks for your response but I am still not sure how my question has been answered.

As I mentioned, the performance WITHOUT KMS and using EXA is 800fps. UXA and XAA etc. DONT work because the performance is derisory.

The evidence is there and I was wondering what is going on.

bangkok_manouel

Member

From: indicates a starting point

Registered: 2005-02-07

Posts: 1,556

Re: no problem more of a question on X11/intel and 2.26/i915 module

With GEM and UXA being mature it looks like the support for XAA and EXA are gonna be dropped sometime soon.

FTR, already dropped in 2.7.99.1

keratos

Member

Registered: 2008-04-27

Posts: 138

Re: no problem more of a question on X11/intel and 2.26/i915 module

As I understand GEM is Intels API and UXA is the acceleraton method developed by Intel. Are these both contained within the Intel driver? What X server and Arch kernels support this Intel driver and what is the current name/version of the driver I need?

I cannot understand why UXA is soooo slow and an unmodified (stock) kernel+intel driver+EXA is twice as fast as the 'newer' UXA+intel (GEM)

combuster

Member

From: Serbia

Registered: 2008-09-30

Posts: 711

Website

Re: no problem more of a question on X11/intel and 2.26/i915 module

Currently UXA is slow and have some bugs primarily because of a kernel related issues wich are going to be solved in 2.6.30 kernel. Performance is not a disaster, glxgears is slower then with EXA but in real 3D apps the difference is not so great, urban terror performace is almost the same. This should answer your question regarding performance.

GEM and UXA is automatically enabled when u enable KMS and it works with 2.6.29 kernel and 2.6.3 xf86-video-intel. With 2.6.29 kernel and 2.7.0 video-intel driver there is an issue with tiling wich gives a garbled screen in 90% of cases (I think that one of the arch users didn't have this issue so I'm stating 90%). This should be resolved some time soon... There is a workaround to disable tiling in xorg.conf if u want 2.7.0 dispite this...

To sum up, if u want UXA and GEM u can do it now with 2.6.29-1 (current stable arch kernel) and 2.6.3-3 xf86-video-intel , just enable kms and that is it, ofcourse if u haven't enabled EXA manually in xorg.conf, if u dont have any than GEM and UXA is the default...

Performance is bad and there are some quirks but there is no noticable difference between EXA and UXA right now regarding performance in real 3D apps. If u want to wait for a week or two for the 2.6.30 kernel and 2.7.0 intel driver thats ok too...

Hope I cleared it up a little...

Last edited by combuster (2009-04-30 14:14:12)

keratos

Member

Registered: 2008-04-27

Posts: 138

Re: no problem more of a question on X11/intel and 2.26/i915 module

thanks friend.

a lot to take in there so can I summarise your statement:

* UXA and EXA performance is currently bad with intel driver.

* with 2.6.30 kernel + 2.7.0 intel, UXA is far better and works fine.

is this correct?

keratos

Member

Registered: 2008-04-27

Posts: 138

Re: no problem more of a question on X11/intel and 2.26/i915 module

all academic!

I have upgraded my system (pacman -Su) and with kernel 2.6.29 and intel driver 2.7 I now have KMS+UXA working. it truly is fantastic. native framebuffer at boot with superb quality (much better than vesafb) and VT switching is instant.

excellent.