如何仅在一个CPU上运行C ++程序？

Question

I've been reading around about how to check how many CPUs or cores my machine has (MacBook OS X, Sierra, v. 10.12, 2GHz Intel Core i7), but there are many different answers, for example here:

How to discover number of *logical* cores on Mac OS X?

what I would need though is to make sure that my C++ program runs just 1 one CPU (and, if possible, only on one core, ie, without scheduling, ie, my program should have a dedicated core to run on => I'm not sure how my Mac OS X architecture is actually organised).

I am not sure if this should be done at implementation, compilation or execution level. I've seen people talking about taskset for Ubuntu, but I'm not sure if that's the right tool for me (maybe it does not even exist for Mac OS X).

Note: if you feel this question should be asked in another Stack Exchange's website, just tell me, and I will move it to there. Actually I would like that my solution is cross-platform, so maybe this is not the best place to ask this question.

Answer 1

Processes are scheduled, the idea of a non-scheduled process is an oxymoron.

That said, restricting yourself to one CPU is pretty much the default in C++. main starts on one thread, and unless you create additional threads that's all you get.

You mention that you want a "dedicated" core. There's the idea of pinning a thread to a core, which sort of achieves that, but you can figure out what happens if two programs pin themselves to the same core. Another core might be fully unused while the two programs share that pinned core. This is more of a feature for supercomputers, where cores do not have uniform access to memory, and you should match CPU core and memory allocations.