Unreal Engine 4 Understanding Net Dormancy (With Examples) 

This is a tutorial on how net dormancy works and how to use it.
Net dormancy is one of the best ways you can use to optimize the performance of your server, net dormancy mainly concerns replication.
The server constantly checks for properties to replicate and that could eat up your performance if you have a lot of replicated properties, certain actors could be doing a lot of work when no player is interacting with them for a long time instead of going dormant until needed.
Check this live stream from Epic which talks in details about net dormancy here: • Networking in UE4: Ser...
If you have any questions let me know.