Question

Exactly how do the threadpool in TPL work? Several blogs says that it works like:

• The thread first checks its local queue
• The thread then checks the global queue
• And at last the thread checks the surrounding local queues

However, the book Concurrent Programming on Windows by Joe Duffy, says that it works like:

• The thread first checks its local queue
• The thread then checks the surrounding local queues
• And at last the thread checks the global queue

Who’s right?

Answer 1

The blogs seem to be correct in this case;

it first looks at the head of its local queue, then in the global
queue, and then in the local queues of other threads.

Source: MSDN, see “Work Stealing”