Quick answer: Unreal Mass Entity replication producing 4KB-per-tick packets when only 100 entities updated? Batch size capped too high - tune mass.Net.MaxEntitiesPerBatch.
1000 mass-entities; 100 update per tick. Each batch is 4KB even though deltas are small.
Tune batch size
mass.Net.MaxEntitiesPerBatch 32Smaller batches = more packets, each fitting MTU better. Eliminates fragmentation latency.
Use delta encoding
Mass supports delta-replicated fragments. Mark with the delta trait; replication sends differences only.
Profile per-system bandwidth
NetProfile breaks down by source. Mass should be one row; sudden growth = batch tuning needed.
“Mass scales well by default. Replication scaling needs explicit tuning.”
Run Mass at expected entity counts on a network simulator. Bandwidth costs surface; tuning becomes informed.