Windows Task Manager Columns - Handles

Question

What is the Windows Task Manager "Handles" column a measure of? File Handles? Or Page File Pointers? Also is it bad for one program to have 8000 handles?

Answer 1

It's a measure of kernel handles. Kernel handles types and the functions that create them include:

• File handles (CreateFile)
• Memory mapped files (CreateFileMapping)
• Events (CreateEvent)
• Mutexes (CreateMutex)
• Semaphores (CreateSemaphore)
• Processes (CreateProcess)
• Threads (CreateThread)

And more than I forget or have never heard of.

8000 for a single process seems incredibly excessive.

Answer 2

8000 for a single process does seem rather a lot, but not necessarily out of the question - it depends on the behaviour. You should think of handles as a special kind of memory - high usage is a possible warning sign, but not if it is stable. If the handle usage is stable, then it is not a sign of a leak, although you might have some optimisation to perform to get it to use fewer handles.