title: How to determine which CPU a thread runs on?
body: <p>Is there a way to determine on which CPU a given thread runs on?
  Preferably in C#, but C++ would do.</p>
  
  <p>The .NET Process and ProcessThread classes don't seem to provide this information.</p>
  
  <p>ETA Clarifications:</p>
  
  <p>We are developing a server application that processes http multicast streams and spawns multiple video encoders. This runs on a system with 12 physical cores, resulting in 24 logical CPUs (hyperthreading). Via TaskManager and ProcessExplorer we have verified that our spawned processes spread evenly over the logical CPUs. However, we are seeing a lot of (kernel?) activity on just one CPU that interferes by eating up unusual amounts of CPU time. We are trying to identify which process(es)/thread(s) are running on this particular CPU. Neither TaskManager nor ProcessExplorer seem to provide that information. If they do, please explain how such information can be obtained.</p>
  
  <p>Otherwise, we are contemplating writing our own tool to get this information. And that is what we need help with.</p>
  
  <p>We know how to change a threads affinity (and we know that there is no guarantee that a thread will remain associated with any CPU, although in this particular case the thread(s) eating up CPU remain associated with only one CPU), but in order to do so, we need to first determine WHICH process/thread needs to be relocated. That is the sole objective of this question.</p>
  
  <p>I hope this helps clarifying the issue.</p>