i915GM very serious GLX problem

[nimnull22]

Hi there.
After recent intel driver update, I decide today to check it and found some problems:
GLXinfo output:

name of display: :0.0
display: :0 screen: 0
direct rendering: Yes
server glx vendor string: SGI
server glx version string: 1.4

GLXgears:

Running synchronized to the vertical refresh. The framerate should be
approximately 1/1936613746 the monitor refresh rate.
165 frames in 5.1 seconds = 32.612 FPS
130 frames in 5.1 seconds = 25.571 FPS
142 frames in 5.0 seconds = 28.374 FPS
XIO: fatal IO error 11 (Resource temporarily unavailable) on X server ":0.0"
after 1010 requests (1009 known processed) with 1 events remaining.


It was ~531 FPS


Please, someone fill a bug for it.

Thanks

P.S.

I use xorg.conf, where I stated to use intel driver and ignore TV1 and VGA1.
There is no any errors in xorg.log

[AdamW]

It's not a bug. Just like the warning message says, it's running synced to your vertical refresh rate. glxgears is not a benchmark, and the FPS numbers it reports do not indicate performance. If you want to benchmark, use a proper benchmark tool.

[nimnull22]

It is not a bug !!!!!

What are you talking about !!!!!
If you don't know, please do not reply.

It is a BUG.

I have second OS on this laptop, it X11 uses XAA acceleration with intel driver:
compiled for 1.5.2, module version = 2.5.0. And output of glxgear is:
3216 frames in 5.0 seconds = 643.117 FPS
3200 frames in 5.0 seconds = 639.851 FPS
XIO: fatal IO error 11 (Resource temporarily unavailable) on X server ":0.0"
after 27059 requests (26887 known processed) with 0 events remaining.


Now I have: 165 frames in 5.1 seconds = 32.612 FPS

It is right now one BIG REGRESSION.
Not step forward, it is two steps backward.
I gonna fill BUG report my self.

---------- Post added at 11:07 AM CDT ---------- Previous post was at 10:49 AM CDT ----------

UXA works a way worse then XAA with i915GM. It works like EXA. With UXA anything I do - switching a workspaces, open programs, or even watch a Divx movie - always Xorg eats CPU about 20-30%.

With XAA on previous x server X uses no more then 15%, and about 5% then I switch workspaces with opened programs.

UXA - it regression, and one big mistake, developers shouldn't mix new card together with old, or if thel like to have one driver for every card, they have to leave old and good acceleration modules. XAA worked perfect, and every one knew about it.

So i can say only one thing - EXA, UXA - step backward for i915.

[AdamW]

Please read what I wrote. glxgears is not a benchmark. The fact that it is running 'slower' does not indicate anything at all about the performance of your system, simply that glxgears now runs synced to the vertical refresh of your monitor and cannot possibly run any 'faster' than that.

From the other stuff you say it seems you are being hit by some kind of bug, but your glxgears result has nothing to do with it. The glxgears fps number means absolutely nothing. We would stop glxgears reporting fps numbers at all, but then instead of using glxgears fps as benchmarks, people would complain that glxgears is broken...

[nimnull22]

TWO (2) weeks ago before I have update Intel driver (or may be it was kernel - I am not really sure what can cause problem); One month ago before I have changed OS to Fedora 13 - glxgears shows proper FPS, compiz works. But now you are saying that it is broken.
You can confuse your self and may be other people, but not me, because first thing that I have done in Fedora 13 after update - I checked glxgears - and got 530 FPS.
It did work.

And now even VESA driver, gives me better FPS, then intel driver.
But compis is something really awful - window resize takes 50% CPU usage by Xorg.
Looks like UXA now in Xorg = software acceleration.

---------- Post added at 06:49 AM CDT ---------- Previous post was at 06:21 AM CDT ----------

And anyway, it you right and glxgears really is synchronized to the vertical refresh, I have to see smooth rotation of those gears. But I see their rotation with frequent stops.

I will check other programs.

---------- Post added at 07:02 AM CDT ---------- Previous post was at 06:49 AM CDT ----------

And also, few day ago I specially make a test - I opened two "OpenOffice Writer" windows with some text in them.
And just simple switching between those two windows already makes Xord use CPU up to 30% - what is this????
Where is 2D acceleration, where?
The same when I do "hide" and "show" from tray. The same 25-30% Xorg CPU usage.
Card does nothing, Xorg reads memory and draws everything, it is not acceleration. It is not acceptable for laptops.
As I said before UXA inherit all from EXA, and for i915 it works awful.

[nimnull22]

So, after upgrade:
kernel-PAE-2.6.33.3-72.fc13.i686
xorg-x11-drv-intel-2.11.0-3.fc13.i686
2D looks like works quickly. Noticeable quickly.
But still compiz works, but not really good - not smooth.

Also I download Quake 3 Demo and got the same FPS - nor more then 50.
May be glxgears is broken but it shows the same FPS.
I do not know what to say in Quake 3 demo - no more then 50-60 FPS, no matter what screen size 640x480 or 1024x748.

I would like to hear some comments about it, because I really want to know how to check 3D.

Thanks

[AdamW]

Quake's likely doing the same.

Think about it: if your card was suddenly so slow it could only manage 50fps on glxgears, would it be able to manage 50fps on Quake, given that Quake's about 5,000,000 times more complex than glxgears?

Nope. Hence, the reason the fps doesn't go higher is because they're running synced to the vertical refresh. There may be a way to disable this for Q3, I'm not sure off the top of my head though.

[nimnull22]

Thanks. I understand about vertical refresh rate. And someone already added explanation to glxgears output - to prevent farther questions.
I also understand that it is quite reasonable to show Frame per Second = vertical refresh rate, but it is a bit confusing.
What is the Frame Per Second value then? And why it depends on vertical rf.?
It is not right.

i915 is not for 3D games, and I personally do not use much of 3D at all, I do not compiz - although it works quite good on OpenSuse 11.1.
But you know, it is necessary sometime to test OpenGL, and I was trying to find small utility in fedora repositories - without luck unfortunately. Games is not for test.
Should be a normal test utility. How to find out real productivity of 3D acceleration?

---------- Post added at 07:03 PM CDT ---------- Previous post was at 06:08 PM CDT ----------

Ok, if glxgears now shows vertical refresh rate, why the hell it changes.
I have from 12 - ~60, and the author wants to say that my vrr changes from 12-60. More important that if I do not move my mouse around screen "FPS" is minimal, when I start move the mouse "FPS" goes up to 60. But why, what if I want glxgears draws picture on 60 always. It just can't be the truth.
I and probably many people now want to know some explanation, what does it show, and where is real FPS, which video card produces?

Thanks

[Maryyy]

Well, I don't have Intel, so how to disable vsync here is unknown to me. I don't use Compiz either, but when I was playing around with it, there was some setting for that, or at least for screen refresh. The reason I mention Compiz is, that if Compiz itself is synced to vertical refresh, then it's very likely that OpenGL app running in window will too, fullscreen ones may not.
Anyway, if my memory serves me well, most Quake like engines (and their source ports) have something like r_swapinterval setting for vsync. So r_swapinterval 0 in Q3's console shoud do it, followed by something like vid_restart or r_restart, I don't remember Q3 in this regard. Anyway, I think that it's the default, so it may be needed to somehow get rid of vsync on the card itself and simply disable compiz altogether after that, just to have clean base to start with.

BTW, if you want REAL OpenGL benchmark, than go for SPECviewperf. Runs just fine, but you'll need csh or tcsh for that matter, it'll not work with bash (unless there is a newer version which does).

As for the real fps, real fps is the top the card can produce with vsync off. Card can easily do 200fps e.g., but if vsync is on and your monitor's refresh is let's say 60hz (most LCDs), it'll never exceed those 60fps, because card is waiting for your monitor to finish the frame and then starts drawing another one, unlike with vsync off, where the card simply pours the frames to the output w/o checking if the previous frame finished on the monitor or not, hence vsync limits your fps drastically.

So try to find a way how to disable it globally on the card, it should be possible somehow.

[nimnull22]

Thanks.
With vsync everything is clear.

But can some one explain WHY glxgears and game shows less then VRR.
If video card runs synced to the vertical refresh and glxgears does the same - WHY I see 12, 20, but not 60FPS always.

My card can do 600 FPS - but it doesn't make any difference, my laptop LCD can only show 60 FPS. And I want to have them. Why can't glxgears and quake renders with VRR=60, it is less then that? I really sure that actual refresh rate is 60, because it can't be 12 or 20. It is a OpenGL program manages to render less then VRR, and question is why?

Please, I would like to know an answer.

Additional information.
I can only get ~58FPS in glxgears when at the same time in other window movie plays. Normally I have ~25 FPS - this is not good. And that is why compiz looks ugly and is not smooth - looks like it also renders at 25 FPS.

[AdamW]

Ah, I think I know what bug you have now:

https://bugzilla.redhat.com/show_bug.cgi?id=582861

please have a look at that report.