load balancing

rehan999 · 06-21-2009, 11:35 PM

Greetings

I have a linux box with Core-2 Duo 2.4Ghz processor.

If i run an application the CPU load should be equally divided between all the processors.

how?PLease advise

Regards

kirukan · 06-22-2009, 12:48 AM

Your application should have ability to handle multiple threads, then only all cores handle the load.

rylan76 · 06-22-2009, 12:50 AM

I think most recent kernels does it this way anyway?

On my FC11 system, with gkrellm loaded, you can clearly see that if a demanding application is running, the kernel splits it evenly between the two virtual cores of my P4 HT CPU - in more or less second long intervals, each core takes a turn running the active application...

Hypothetically, I think this means that if you have more CPUs, the kernel will "spread" the application's running even more "thinly" over all of them.

kirukan · 06-22-2009, 01:23 AM

And check what is smp (Symmetric multiprocessing), if your application not support with smp then load wont handle by all cores, please if i am wrong correct me
http://en.wikipedia.org/wiki/Symmetric_multiprocessing

chrism01 · 06-22-2009, 06:41 PM

Basically, the current kernels eg 2.6.x will automatically handle multiple cores at the OS level. The load won't be exactly balanced due to the dynamic nature of the workloads, but on average it should even out.
An individual application cannot be split this way unless it was written/compiled with threading as part of the design.
It will however get moved around various cores by the OS.