It's hard to say. It looks like the
Microsoft.VisualStudio.WebHost.Connection type is a strongly-typed wrapper
over a socket connection. If your load test is establishing HTTP/1.1
sessions, I'd expect the connections to stay "alive" because connections
persist in HTTP 1.1 until they are closed by the requester.
But if you want, you can send the ANTS results to Red Gate support and
we can use them to trace the object references back to the root. The
Instance Categorizer is meant to show how the objects are rooted... http://www.red-gate.com/products/dotnet-development/ants-memory-profiler/features/instance-categorizer