Can I disable one or more processors in multiprocessor machine?

Question

I have server with two quad core processors, installed windows 2003 standard edition. I want to test an application on a machine with single quad core processor and I want to use this machine so how can I disable one of two processors?

I prefer a software solution but if the only solution is a hardware no problem.

Answer 1

Quick and dirty: Use task manager, select the process, and use the affinity bits to disable any cores you like for that process.

Very useful for debugging, too.

Answer 2

You can set the "Affinity" of a running process / application to only execute on one core:

Go to task manager, select the process in question, right click and select "Set Affinity", then choose just one core.

Answer 3

The solution will normally use to test the application which need rely on these kind of requirements is VMware (or equivelant virtual machine software e.g. Vitrual Box etc.)

This is a proper solution for test an application rely on the hardware environment as you can allocate the CPUs and Memory.

Answer 4

Or you can try it from the application itself (if appropriate) with Process.ProcessorAffinity.

Answer 5

Edit boot.ini, add /NUMCPU=1, and reboot. This will instruct Windows to ignore all but one core/CPU.