multithreading and multicore

[Doom Machine]

i'm thinking about upgrading to core 2 duo, theres alot more multithreaded apps and games comming this year.

since amd's 4x4 is comming next year, i wanted to know, does say a game or app thats multithreaded have to be designed specifically for a certain number of cpu's?

like if say the game oblivion which can work with 2 cpu's, work better or work at all with 4 cpu's....if not then it could be a couple more years before anything can support the 4x4 and i'm safe to upgrade to 2 cores yes?

 

[kamper]

It doesn't have to be designed for any specific number of cpus. However, it won't benefit from the extra cores unless the developpers have broken the work up into enough threads.

 

[XZeroII]

Originally posted by: kamper
It doesn't have to be designed for any specific number of cpus. However, it won't benefit from the extra cores unless the developpers have broken the work up into enough threads.

Or if you want to run more than one thing at a time. Like video encoding while you play a game.

 

[DaveSimmons]

An E6400 can already max out a 7900GTX in SLI, so until video cards advance another generation or two it doesn't matter how much parallelism is coded into the games the quad core would just go back to twiddling its pins a little faster.

 

[Bateluer]

Originally posted by: DaveSimmons
An E6400 can already max out a 7900GTX in SLI, so until video cards advance another generation or two it doesn't matter how much parallelism is coded into the games the quad core would just go back to twiddling its pins a little faster.

I don't think thats entirely true. Additional cores will be used for phsyics processing and the like. I'm not a programmer though.

 

[DaveSimmons]

It's true that someday some games will make good use of more than 2 cores, but I'd guess that's at least 3 years away from now.

Any optional physics or AI added any time soon will be written to gain most or all of its value from using the currently idle second core of dual-processors, not to need 4 cores.

The exception will be game extras paid for by intel or AMD as a marketing tool and intentionally crippled with a check for the quad processor. Those extras would probably have run fine on just a dual core.

 

[biostud]

Alan wake apperently spawn 5 threads (unreal 3 engine), although not all are equally demanding:
http://anandtech.com/tradeshows/showdoc.aspx?i=2841&p=2

The game will actually spawn five independent threads: one for rendering, audio, streaming, physics and terrain tessellation. The rendering thread is the same as it would be in any game, simply preparing vertices and data to be sent to the GPU for rendering. The audio thread will obviously be used for all audio in the game, although Remedy indicates that it is far from a CPU intensive thread.

 

[Kromis]

Great for servers, I'll tell you that. But uhh...we probably don't need quad core, so don't worry about it much.

 

[BFG10K]

Alan wake apperently spawn 5 threads (unreal 3 engine), although not all are equally demanding:

Just because the game spawns multiple threads it doesn't automatically mean a performance gain on MP systems.

Most games are multi-threaded yet very few actually gain performance on MP systems. I think even GLQuake has more than one thread.

 

[skace]

A properly written multithreaded game will make use of as many cores as it is allowed. If you have the proper updates to XP you can also define affinities with your quad cores allowing you a greater range of flexibility. IE, one application could be using cores 0,1,2 and another could be using 2, 3. Etc.

 

[gsellis]

Originally posted by: XZeroII

Originally posted by: kamper
It doesn't have to be designed for any specific number of cpus. However, it won't benefit from the extra cores unless the developpers have broken the work up into enough threads.

Or if you want to run more than one thing at a time. Like video encoding while you play a game.

There is a flaw with that though. In XP, First in wins on the GPU memory side. Trying to have multiple games loaded can run the system out of video memory (this is a specific issue MS has tried to resolve in Vista). And good encoders will max out CPUs. Tsunami does (see Rigs but cliffs are - running a dual HT Xeon wkstn).

And everyone is running multicores these days. We just forget to add the GPU to that count

 

[biostud]

Originally posted by: BFG10K

Alan wake apperently spawn 5 threads (unreal 3 engine), although not all are equally demanding:

Just because the game spawns multiple threads it doesn't automatically mean a performance gain on MP systems.

Most games are multi-threaded yet very few actually gain performance on MP systems. I think even GLQuake has more than one thread.

from what is mentioned it sounds like the physics will use most of one core, and the rest will probably run fine together on a single core, so a dual core/CPU setup will be very beneficial if not requiered. Ofcourse they can't make a game that requires a 4 core setup, but it might help to reduce stutter specially when data needs to be loaded from the harddrive. I'm just guessing.

 

[Doom Machine]

i recall microsoft saying that the xbox360 as of now only runs 1-2 cores and 3 core games wont come out for a couple years, so figured i'd make sure before thinking of waiting for 4 cores

so far my single core athlon64 4000 does just fine, it plays any game out there well so not even sure why i want to upgrade, guess i have money burning my pockets
first i need to figure out how much performance gain i would actually have over my current setup as when crysis is released i must have graphics maxed