> The OS will switch contexts regardless of how many threads you have With IRQs pinned (via CPU mask given to the kernel at boot time) and application process

> The OS will switch contexts regardless of how many threads you have With IRQs pinned (via CPU mask given to the kernel at boot time) and application process pinning, there will be no preemption of the application process. > Even with zero threads the OS will be context switching between processes anyways No, this is what pinning is explicitly for. > What you're trying to say is that threads might get starved due to imperfect scheduling No, you've misunderstood