The legacy driver had documentation for the various connection handling behaviors across multiple versions (see: here). We should have similar documentation for the new driver.
In particular, this will need to cover:
- Persistent sockets (but not topologies) in PHPC versions before 1.2.0, which used PHP streams for socket handling and SSL
- No connection persistence in HHVM versions before 1.2.0, which used libmongoc for socket handling and SSL
- Persistent mongoc_client_t (sockets and topolgies) in PHPC and HHVM 1.2.0+, which use libmongoc for socket handling and SSL
Additionally, this documentation should discuss how persistent connections are hashed in 1.2.0+ and explain reasoning for not providing the same API found in the legacy driver (e.g. a close() method).