Unity uses an older Mono (2.10 I believe) which has a poor GC that's not even deterministic, so you can easily suffer memory leaks. It is also not generational.

Unity uses an older Mono (2.10 I believe) which has a poor GC that's not even deterministic, so you can easily suffer memory leaks. It is also not generational. Newer versions of Mono come with a much better GC.