Mac Pro Multi Core CPU usage.

Only certain versions of windows can even utilize dual processors, much less multiple cores. An OS X game will use multiple cores for the most part if it is written to do so.

And why would you need eight cores to start up? It's about 20 seconds, anyway...

 

Oh, yes. It's distributed. There was a thread about running two copies of HandBrake simultaneously and they took all eight cores to only about 60%. There's enough power there to choke a horse with enough left over to make its rider clear his throat.

 

As an example, if you develop large software projects, XCode will automatically use all eight cores while compiling. That means it can compile eight source files simultaneously. If you have a tiny project with two source files only, it makes almost no difference (but then it takes almost no time anyway). If you have a project with 2000 source files, compiling them will run eight times faster.

 

OSX is designed to distribute the work load across multiple CPUs.

The hard drive speed is usually the limiting factor on how fast things can work (As in the case of the Handbrake example).

 

Nope. He just had two Superdrives (two drives, anyway; it doesn't need to be an Apple drive), and he copied HandBrake and opened two of them at once (just name it HandBrake 2 or something).

In OS X it's distributed. All eight cores are used for all Apple apps. Third party apps will run as many cores as they are designed to see. For example, HandBrake is written to be able to use all eight, but I think CS3 or something like that can only use four.

Again, it's up to the vendor, but Apple apps know how to make the most of their own hardware.

 

I'm not 100% sure what this means, but it made me laugh out loud.

If you're referring to this thread: http://forums.macrumors.com/showthread.php?t=447186, he has "only" a quad-core machine with 4 gigs of RAM and he's getting incredible handbrake performance out of it.


James

 

Yes indeedy. Compiling large projects on a Mac Pro is truly wonderful.

"make -j 8" is your friend

 

Depending on which Apple application you're talking about, they may or may not "know how to make the most of their own hardware." The Final Cut series of video editors, for instance, will not make decent use of all available cores. Oddly enough, QuickTime Pro, will. Why that's the case is anyone's guess.

I've written this in other posts: OS X has the foundation in place for applications to take advantage of more than one core. In the end though, that's all the OS can really do: provide that foundation. It's really up to the individual applications to make use of that foundation. And in order to do that, the application must be threaded.

It sounds like Handbrake (never used it) is properly threaded. QuickTime Pro is properly threaded. Photoshop does a decent job of threading as well. Final Cut Express.. not so much.

Unfortunately, there's no real way to tell whether an application will make good use of all those cores without trying it first. It's not something a vendor will put on a box or package. It's not something you can really look up online (other than reading folks' experiences with the application in question).

As far as Windows and games are concerned: anything more than 2 cores is a waste. No game that I'm aware of is currently written with threading in mind, so they can't really take advantage of multiple cores. At best, having one core run the game while a second one watches over the rest of the machine is probably all you can expect.

jas