How many instances of the CLR are running?

Question

There is a simple Hello World Console Application. We compile it and get an assembly (EXE). The EXE is copied into 5 different folders and run from each of the locations. How many instances of the CLR are running when the 5 copied instances are running at the same time?”

Answer 1

It runs 5 different processes each with its own CLR instance.

Answer 2

Each physical process gets its own copy of the CLR because each is hosted separately. Thus if you create 3 instances of your .NET app you will have 3 copies of the CLR running. Each process will have at least one AppDomain. Where it gets sort of tricky is with domain-neutral assemblies. Domain-neutral assemblies, like some of the system assemblies, are actually shared across AppDomains. This reduces the footprint of the CLR.

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