Starting in MongoDB 4.4, hedged reads speed up your slowest reads, approaching the latency of average reads. This makes query latency more predictable and less variable on systems, even as the workload changes. For certain read preferences, MongoDB will dispatch another read to another available node in the replica set. Reads against a sharded collection using a read preference of "nearest" will be hedged automatically.
After this session, you will understand exactly how sharded hedged reads work and how to enable or disable them for other read preferences.