In our game Command Authority, we work with large server sizes. We recently released an update expanding our server size from 150 to 170, with an average player count (accounting for social slots) of 160.
We saw a massive degradation in performance with this change. The biggest way this manifested from the player perspective was streaming failures - terrain and parts would take a long time to stream, and the streaming distance would only be 20-30 studs (regularly 1,000).
We confirmed that this was not the cause of any memory leak or higher-than-usual script usage. Additionally, it was pretty consistently tied to the player count: servers which dropped back below 150 players would immediately resume normal performance, and a server reaching maximum size would almost immediately start experiencing streaming issues.
While we understand that at higher server sizes games tend to reduce performance, the reason I’m reporting this as a bug is due to the massive and nearly instant degradation in performance seemingly tied to exceeding the 150 “safe” player count number.
The game is Command Authority: Command Authority: Military Roleplay - Roblox, and is now back down to a 150 player count.