Where are my managed threads in W3WP

Question

I create some managed threads inside an asp.net application (System.Threading.Thread). Each thread creates a row in a database and deletes it after the work is done (~3-5 minutes).

When I look thread count of w3wp in task manager of windows, the thread count is less than what I expect. For example if I have 100 running jobs according to database, there are 50 threads in w3wp. It is very fluctuating and sometimes it's one to one.

Does thread count in task manager count managed threads? If yes, then where are my threads ?

Answer 1

An operating-system [thread] has no fixed relationship to a managed thread, because an unmanaged host can control the relationship between managed and unmanaged threads. Specifically, a sophisticated host can use the Fiber API to schedule many managed threads against the same operating system thread, or to move a managed thread among different operating system threads.

• Source: Managed and Unmanaged Threading in Microsoft Windows