How good is Windows at distributing tasks between cores?

Question

I have two cores in my computer, and i want to know this: When my computer is running several programs at once (firefox, downloading, uninstalling, etc.), how well is windows distributing that across multiple cores?

Answer 1

Windows does a good job of distributing the load when the problem is multiple, single-threaded processes both trying to use as much CPU as possible.

However, the situations you describe are more limited by your hard drive's ability to read (or write) different things at the same time. Adding a few more cores wouldn't help you at all.

Answer 2

It's going to depend on the version of Windows. Here's a video describing how Windows 7 improves the dispatcher (scheduler). In short, it does a pretty good job of it.