After diagnosing a customer issue (SERVER-45137) where Top was allocating memory to record collection information and not deallocating it once the collection was removed, I believe we should set out to improve the 'Top' command in regards to its data management.

Forgetting to clear collection information from Top comes with consequences, such as running out of memory for long enough running processes. We should have a mechanism in Top that guarantees the collection information will be cleared once the collection is dropped. Making the Top data as a decoration on the collection is one way we could ensure this, it would even handle a collection rename for us.