Context

Currently the Go driver calls RTTMonitor.Stats for every operation on both v1 and master. That call acquires a read lock and performs a series of calculations to get an RTT statistics summary to add to error messages. Ideally we shouldn't call that method on every operation.

Definition of done

• Change the Operation.Execute code to only call RTTMonitor.Stats when generating an error value, not on every request.
• (Optional) Consider replacing the RTT values read on every request (e.g. EWMA, Min, P90, etc) with atomic.Value to avoid using an RWMutex (see GODRIVER-3094).

Pitfalls