Multiple Instances of w3wp.exe

Question

I don't understand why there are two ASP.NET w3wp processes in Task Manager when I only have one website and one application pool. Why are there two processes running? I have Googled this and looked on MSDN but cannot find an answer.

I am trying to debug a memory leak in an application. I understand the concept of threading and multiple threads living in a process, but I do not understand why there are multiple processes.

I am specifically asking what scenarios can cause more than one process to run.

Answer 1

Look at the Advanced Settings of your application pool for this section, and make sure the indicated value is set to 1: