Running on one core (Linux)

I know that when running on multi-core machines on Linux, you can run your Nexuiz/Xonotic on one core using "taskset" like so:

Code:

taskset -c <cpu number> <Nexuiz/Xonotic startup command>

...with the idea being that these games are single-threaded, meaning running without affinity will only add overhead (iterating unnecessarily over all the processors when one will do).

Does anyone do this often? What results do you see? I'm curious - I did it once, but I'm not sure I was looking for the right things. Would I look for FPS improvements alone? Decreased overall CPU utilization?

Anyway, any feedback would be helpful.

I know that when running on multi-core machines on Linux, you can run your Nexuiz/Xonotic on one core using "taskset" like so:

Code:

taskset -c <cpu number> <Nexuiz/Xonotic startup command>

...with the idea being that these games are single-threaded, meaning running without affinity will only add overhead (iterating unnecessarily over all the processors when one will do).

Does anyone do this often? What results do you see? I'm curious - I did it once, but I'm not sure I was looking for the right things. Would I look for FPS improvements alone? Decreased overall CPU utilization?

Anyway, any feedback would be helpful.

On Windows it makes the game appear more fluent, the fps stay about the same and the overall-cpu usage also stays the same (100% of one core or 25% of all)
It helps against micro-stutters (similar to those on multi-gpu systems).

It should be the same under linux (although this depends on how the scheduler works there)

I know that when running on multi-core machines on Linux, you can run your Nexuiz/Xonotic on one core using "taskset" like so:

Code:

taskset -c <cpu number> <Nexuiz/Xonotic startup command>

...with the idea being that these games are single-threaded, meaning running without affinity will only add overhead (iterating unnecessarily over all the processors when one will do).

Does anyone do this often? What results do you see? I'm curious - I did it once, but I'm not sure I was looking for the right things. Would I look for FPS improvements alone? Decreased overall CPU utilization?

Anyway, any feedback would be helpful.

On Windows it makes the game appear more fluent, the fps stay about the same and the overall-cpu usage also stays the same (100% of one core or 25% of all)
It helps against micro-stutters (similar to those on multi-gpu systems).

It should be the same under linux (although this depends on how the scheduler works there)

Made no difference. The game is still EXTREMELY glitchy on Ubuntu 10.10 (but that's maybe because it's just an alpha version). The mouse cursor doesn't even work right, when I move the mouse to one position, it 'jumps' back a second later. Very difficult to even make menu selections. It runs just fine on 10.04 though. I'm running on an 8 core system by the way.

I have a AMD quadcore, and I'm running Ubuntu 10.04. What I have to do is go back to kernel 2.6.31 to get better performance, but I'm guessing it is specific to my hardware wrt the changes Ubuntu made between kernel versions.

Made no difference. The game is still EXTREMELY glitchy on Ubuntu 10.10 (but that's maybe because it's just an alpha version). The mouse cursor doesn't even work right, when I move the mouse to one position, it 'jumps' back a second later. Very difficult to even make menu selections. It runs just fine on 10.04 though. I'm running on an 8 core system by the way.

Do you use compiz? You might want to disable that when playing games.

Do you use compiz? You might want to disable that when playing games.

We could provide an automated installer for /usr/share/xsessions/xonotic.desktop, autodetecting xonotic path.
This way there's no compiz or anything else disturbing in the background...

I'm not sure about this... Those who want that can make their own one-line script to launch xonotic in a separate X session, it's too hacky to provide it officially (painful switching between sessions)

Made no difference. The game is still EXTREMELY glitchy on Ubuntu 10.10 (but that's maybe because it's just an alpha version). The mouse cursor doesn't even work right, when I move the mouse to one position, it 'jumps' back a second later. Very difficult to even make menu selections. It runs just fine on 10.04 though. I'm running on an 8 core system by the way.

Do you use compiz? You might want to disable that when playing games.

I tried turning off Compiz, and it made no difference. It worked when I re-installed Ubuntu though.

Weird... :x

Those who want that can make their own one-line script to launch xonotic in a separate X session, it's too hacky to provide it officially (painful switching between sessions)

Yep, agreed on that. Downstream distributors of the project (like Debian packagers or Ubuntu MOUs) can add those features if they'd like. We can't guarantee much on that front. Perhaps a wiki entry to make it easy for people to run under a different session so would be good, though.

tankmiche - care to explain how you run under a different session? I can take a stab at creating the wiki entry.

Those who want that can make their own one-line script to launch xonotic in a separate X session, it's too hacky to provide it officially (painful switching between sessions)

Yep, agreed on that. Downstream distributors of the project (like Debian packagers or Ubuntu MOUs) can add those features if they'd like. We can't guarantee much on that front. Perhaps a wiki entry to make it easy for people to run under a different session so would be good, though.

tankmiche - care to explain how you run under a different session? I can take a stab at creating the wiki entry.

Sure, put this in /usr/share/xsessions/xonotic.desktop:

Code:

[Desktop Entry]
Name=Xonotic
Comment=Play Xonotic in a standalone X session
Type=Application
Exec=/path/to/xonotic/all run

To try it, and that's the painful transition Mr. Bougo was talking about:

• Same user: logout (sic) and re-login choosing "Xonotic" as the X session in the prompt
  
• With another user: switch user, then login as the other user choosing the "Xonotic" session.
  

Please note: the current solution doesn't work because the "all" script wants to be cwdded in the xonotic directory, there should be a "run" helper script or that limit completely removed.

Or just use this http://freshmeat.net/projects/xgame/

EDIT: well, "just" use this

Thanks to both of you. I will give it a test and create a wiki entry. I feel so useless (not a C programmer, modeler, or mapper), so maybe in that area is where I can contribute

Made no difference. The game is still EXTREMELY glitchy on Ubuntu 10.10 (but that's maybe because it's just an alpha version). The mouse cursor doesn't even work right, when I move the mouse to one position, it 'jumps' back a second later. Very difficult to even make menu selections. It runs just fine on 10.04 though. I'm running on an 8 core system by the way.

Do you use compiz? You might want to disable that when playing games.

No, and it's not weird at all. Even back with my 7950 card I could run compiz (or back then, beryl), at the same time. Compiz does not steal FPS, and even if it did, it wouldn't explain the mouse cursor issue.

My guess is: GLX. The GLX version never worked for me here. Not with beryl, not with compiz(/fusion), not with wmii, not on gentoo, not on archlinux, not ever.
Try the SDL version and it will all be fine.