Lot of GC when receive and send messages

[hardsmoke]

Description

Hi, I'm experiencing a lot of memory allocations when sending (NetworkMessageManager.SendMessage) and receiving messages (NetworkMessageManager.ReceiveMessage). These allocations occur when sending RPCs, as well as due to built-in networking components (e.g., NetworkTransform). Profiling was performed by the host using a debug build of IL2CPP with the deep profiler. There were five people (including the host) logged on to the server at the time.

Screenshots

Environment

• OS: Windows 11
• Unity Version: 6000.3.16f1
• Netcode Version: 2.11.2
• Netcode Topology: Host - Client

[EmandM]

The middle screenshot is unfortunately a known issue. It's due to the current design of NetworkTransform. We're working on removing it, but unfortunately it requires a pretty deep re-work of NetworkTransform. It's a tricky piece of work that is unfortunately likely to cause some regressions

The other two GC allocs look more solvable.

The first one is inside a call of Activator.CreateInstance. The only NGO code that calls this method is inside Editor code, so it's unlikely to be the culprit here. Do you have any custom serialization configured in your project? Common culprits can be any INetworkSerializable types or NetworkBehaviours with OnSynchronize implemented.

The bottom screenshot is coming from an RPC send. Some of NGO's automatic serialization of RPC parameters will make GC allocs. Are you passing any parameters with that RPC? If you can share the RPC code here we might be able to help figure out how to get the same functionality without the GC allocs.