Spin all threads of a CPU.

spinCpu.cpp

/*
 * spinCpu: Spin all threads of a CPU.
 * This is useful for testing how things behave when the CPU is fully utilised.
 * Copyright 2022 James Teh
 * License: Mozilla Public License version 2.0
 */

#include <iostream>
#include <thread>
#include <vector>

using namespace std;

void spin() {
	for (; ;) {
	}
}

int main() {
	auto nThreads = thread::hardware_concurrency();
	cout << "Using " << nThreads << " threads" << endl;
	--nThreads; // Main thread is 1 thread.
	vector<thread> threads;
	for (int t = 0; t < nThreads; ++t) {
		threads.push_back(thread(spin));
	}
	spin();
}