Crashes on Hyperthreading / Multicore and 100% CPU usage

[NightTwix]

i play on a multicore cpu all the time (Intel).
when i stared playing i barely crashed.
Then there came a long period of LOTS and LOTS of crashed. But those were gone after an update a few weeks ago.
nowadays i never crash any more (maybe once or twice a week).

The crash issues i had were IMHO caused by other reasons (bugged linuxclient, broken ressources)

I know how frustrating constand crashes are.
All i can say that nowadays the game runs really stable on my box.

Its true that the game doesnt take use of the multiple cores directly, but its the kernels job to distribute the OS ressources. The way it works right now i can easily compile stuff in the background and play regnum at the same time.
Im sure it impacts overall performance negativly if the game would span across multiple cores.
Even the 100% cpu/core usage is perfectly fine, it should be that way but its not easy to explain why.

I wonder which setups cause the problems.
There were other threads about issues with AMD multicore CPUs. Also ATI graphiccards seem to cause lots of problems. could also be a combo of things.
Or could even be good old windows that doesnt handle multicore computing properly

[Myxir]

Oh my god. I just read this thread in the gamigo forum.
http://regnum-forum.gamigo.de/showthread.php?t=1560
Two things I wondered about.
First:
Some people report that Regnum uses 2 cores but not everytime, on quad cores it works mostly correctly. According to the posts it seems to happen to the linux client very often that it does not use the available cores. I cannot believe this. Regnum NEVER used two cores for me.
Second:

Originally Posted by niclam

Regnum supports dual core from scratch.
I just spoke to one of our technology guys and he said that AMD dual core pcs have several compatibility issues, and that it happens with a lot of games. He also mentioned that there are several hotfixes available for windows and from AMD/Intel that can help bring more stability with games.

This issue seems to be happening more with AMD than Intel. I have a dual core in my house (Intel) and I regularly play Regnum with no problems whatsoever (I have Windows Vista). Several employees at NGD also have dual cores machines.

You can help me further by getting more precise stats about this. Which processors are they using, windows version, video board, etc.

http://regnum-forum.gamigo.de/showpo...55&postcount=2
I wonder what he means by "supports dual core from scratch". I guess it means that Regnum won't stop working of dual core is detected.

[octopus]

Originally Posted by Myxir

Sorry, but in my oppinion this is crap. Regnum does NOT use the second core. It only uses one. This annoys me very much because of saving energy... Both cores are running at 100% speed but they could run at ~50% if Regnum would use both cores.
One core runs at ~70-90% load and the other has just something about 2-10%.

If you are running Windows, that second CPU is there to run your viruses and spyware. If your second CPU is only running at 2-10%, just wait until you get a few more viruses, pop-ups and other malware, then your second CPU will be fully utilized.

On a more serious note, we have 5 computers that can all run Regnum. Four of them are single-core AMD systems, and on those Regnum has always been stable. On the fifth machine, an Intel dual-core system (and the fastest system we have), Regnum crashes every 5 minutes or so. I haven't tried turning off hyper-threading on it yet, but I've heard that can help. All five run Ubuntu, and all with Nvidia video cards.

[theotherhiveking]

Regnum only uses 1 core, it was designed to use only 1 core.

making it use 2 cores would really damage performance in single core procesors.


When the game is not focused it takes less resources, this is intentionan.

[Prometheus]

Originally Posted by NightTwix

Its true that the game doesnt take use of the multiple cores directly, but its the kernels job to distribute the OS ressources. The way it works right now i can easily compile stuff in the background and play regnum at the same time.
Im sure it impacts overall performance negativly if the game would span across multiple cores.
Even the 100% cpu/core usage is perfectly fine, it should be that way but its not easy to explain why.

I wonder which setups cause the problems.
There were other threads about issues with AMD multicore CPUs. Also ATI graphiccards seem to cause lots of problems. could also be a combo of things.
Or could even be good old windows that doesnt handle multicore computing properly

I'm a software developer and I don't think that the 100% CPU usage is necessary.

I can confirm that running the game on only one of my CPU cores (intel core 2 duo) works for almost 4 hours (then my RAM is full and Windows starts swapping and the game crashes after that), while running on both the game crashes in the first 15 minutes or so. I have thourogly tested this in the last 7 days or so.

Even if the game doesn't seam to use the second core, it crashes when both are enabled and I can proof this (at least for my own system). I think that we have nailed down one problem that is pretty independed of the others.

I can't say much to the other graphics card related problems, but I definitely have a problem with multiple cores.

[Prometheus]

Originally Posted by theotherhiveking

Regnum only uses 1 core, it was designed to use only 1 core.

making it use 2 cores would really damage performance in single core procesors.


When the game is not focused it takes less resources, this is intentionan.

Where do you have this information from?

A well written multi-threading application will run optimally on a single and a multi-core system. I'm pretty much sure that this is true as I wrote such applications myself already

[theotherhiveking]

Originally Posted by Prometheus

Where do you have this information from?

A well written multi-threading application will run optimally on a single and a multi-core system. I'm pretty much sure that this is true as I wrote such applications myself already

I took the information from killeak and surak.

[niclam]

Regnum was designed with single cores in mind. The underlying technology NGD created more than 5 years ago wasn't thought out for multi-cores.

That's why while Regnum stills works on Multi-core CPU's (the compatibility issues are yet to be analyzed), it doesn't use the full extent of it most of the time. When it does, it's because some auxiliary threads have been spawned (i.e.: resource loading).

Regards

[Prometheus]

Originally Posted by niclam

Regnum was designed with single cores in mind. The underlying technology NGD created more than 5 years ago wasn't thought out for multi-cores.

That's what I had expected. I hope you have some time next year to bring a little bit more "threadiness" into the game.

Originally Posted by niclam

That's why while Regnum stills works on Multi-core CPU's (the compatibility issues are yet to be analyzed), it doesn't use the full extent of it most of the time. When it does, it's because some auxiliary threads have been spawned (i.e.: resource loading).

So it may be a problem of thread synchronization? I already had the terrain loader in mind as the culprit.

The only question you didn't answer is why Regnum uses 100% CPU and I still think that the game does some kind of idle loop on purpose that is really unneccesary (and heats up my laptop ).

Otherwise thanks for the clarification and have a good new year celebration

[theotherhiveking]

Originally Posted by Prometheus

That's what I had expected. I hope you have some time next year to bring a little bit more "threadiness" into the game.


So it may be a problem of thread synchronization? I already had the terrain loader in mind as the culprit.

The only question you didn't answer is why Regnum uses 100% CPU and I still think that the game does some kind of idle loop on purpose that is really unneccesary (and heats up my laptop ).

Otherwise thanks for the clarification and have a good new year celebration

More cpu usage = more fps.