ut2004 and amd64 Cool`n`Quiet

[FirechilD]

I just found out something really interessting:

im using an amd64 3000+ (64bit install) and a GeForce 6800GT.
"stat fps" showed me ~47fps - even in 800x600 and normal settings. this was a little bit low i thought ^^

i also have frequency scaling enabled in my kernel (2.6.12-rc2-nitro1) and let it do its job via:
echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
wich is in my local.start

if i do this line as root:
echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
(wich lets my cpu running at 1,8ghz all the time and dont scales it down if its not needed )
i get ~85fps (vsync enabled)

it would be very interesting to hear if someone other as me has (had) the same problem.

[tomato]

Interesting. Are both those frame rates online or single player (I get a massive difference in fps depending). Also, when your computer compiles something does your cpu frequency increase?

Check with:

Code: Select all

cat /proc/cpuinfo

[Aynjell]

Cool n' quiet scales the CPU down to 1GHz I beleive, or at least it does so with my 3200+. So, your frame rates being cut just about in half do not surpise me. When you have half the cpu power, things just don't work the same.

[FirechilD]

yep my cpu frequency is rising at a compile and my fps are tested in single- and multiplayer modes

[Headrush]

Cool n' quiet scales the CPU down to 1GHz I beleive, or at least it does so with my 3200+. So, your frame rates being cut just about in half do not surpise me. When you have half the cpu power, things just don't work the same.

Although my 3200+ starts at 1000MHz, it quickly changes to 2000 once ut2004 starts.
If you want you can modify the ut2004 script to change the cpu frequency scaler to performance before starting the game.
(Its just a script that sets varibales and then starts the "real" ut2004 program.)

[hammy]

I came upon this very same problem, and have been worrying about it for the past few days. I did some tests today with Performance and Ondemand schedulers. Performance gives me ~83 FPS and ondemand gives me 46 fps (max). I put the CPU Frequency applet on my GNOME toolbar and played ut2004 in a window. I noticed that while using Ondemand, the CPU jumps up and down from 1GHz to 1.8GHz a few times during load, and then ramps up and stays at 1.8GHz (I have an amd64 3000) until I exit. I finally gave up on the startup scripts (I was trying to get it to switch to performance and startup, then switch back) and just played some games. I noticed that despite ut2004 running at 40-odd FPS, it sure looked smooth, especially with vsync on. I turned off the FPS display and ran it again with Performance. It felt the same, despite running at twice the framerate. Since there is no way to test framerate outside of ut2004 itself (like with FRAPS on windows), I have to rely on my eye and gut feeling. I suspect that something is set during initialization of ut2004, making some sort of timer think I'm only going at 1 GHz, despite the CPU ramping back up at 1.8. 1.0 / 1.8 = 55.6%. 46 fps / 83 fps = 55%. I realize that ut2004 is very CPU-bound, with all of the physics detail and SSE/MMX optimizations, but the smoothness of gameplay at low "framerates" leads me to believe that it's simply a static multiplier being set at run-time and not changed during gameplay.

Just to test, I set the "userspace" governor and went manually back up and back down during gameplay. Starting at 1.8GHz the framerate was 83fps, setting it to 1GHz did not affect framerate (still displayed 83fps, but felt more choppy). Starting at 1GHz gave me 46fps, which did not change when I set it back to 1.8 GHz (though it felt smoother). Something fishy is going on with the code, but I don't believe it's any more than a surface issue which ought not to bother you unless it affects benchmark runs too (I don't know how to run those with the linux install).

[FirechilD]

https://bugzilla.icculus.org/show_bug.cgi?id=2260

as ryan said - this is not a bug ( but i cant tell what it causes this if its not a bug :/ )