I had intended to begin a new theme in October, but I got an inquiry from a customer last week for which the answer may help others, and it definitely fits into the Free Stuff theme. It can be extremely difficult to understand and solve problems for mission critical IIS applications without a good view of application pool use. IIS7 makes the process of application pool monitoring and recovery very easy in the IISMgr interface. You have access to modify the Process Model in detail. In IIS6 and below, the application pools appear as w3wp.exe processes in Task Manager. But it’s not clear which w3wp.exe process represents which application pool. Fortunately, Microsoft again provides a VBS script to figure that out. That’s just half the battle, though. Once we know the specific process that supports each application pool we want to get some detailed process statistics. We could populate several WMI queries with the process PIDs, but an easier, more efficient method is to download and install Microsoft’s Sysinternals PsList.exe utility. It’s free and provides all the process and thread information we’ll want.

How do we identify our application pool processes?