One can indicate to the OS that the current thread can be rescheduled so that other threads can run instead. For this, one uses the std::this_thread::yield() function. The exact result of this function depends on the underlying OS implementation and its scheduler. In the case of a FIFO scheduler, it's likely that the calling thread will be put at the back of the queue.

This is a highly specialized function, with special use cases. It should not be used without first validating its effect on the application's performance.