com.unity.transport 0.6.0-preview.7

Hi all,

I can't find a better place to post this - it is not in relative to the netcode package itself, but the transport package. Please let me know if there is a better place to post it!

I am currently experimenting with the fragmentation pipeline stage so that I can send larger packets. I am currently experiencing a crash (stacktrace below) which happens at seemingly random places. I *think* it is when packet size is between 1350 and 1400, however I am still looking into it in more detail.

Whilst I investigate further, I thought I would raise a few questions that I had so far, and then update the post if I discover anything new.

1. Can the fragmentation stage be used in combination with the reliable sequenced and unreliable sequenced stages?

2. Where in the pipeline should the fragmentation stage go? My gut says it should be the final stage, however we also have a simulator stage and I think that should be the final stage, so it guess it should be the 2nd to last stage?

The below stack trace is when sending using a combination of unreliable, fragmentation and simulator stages. Unreliable is the first stage, and I have tried fragmention and simulator in either order however I still get the same crash.

Any help would be greatly appreciated!

Cheers,
Andy

Code (CSharp):

1. ========== OUTPUTTING STACK TRACE ==================
2.  
3. 0x00007FFF23C4F076 (lib_burst_generated) [C:\BuildAgent\work\69a805ec5677a170\Library\PackageCache\com.unity.transport@0.6.0-preview.7\Runtime\Pipelines\FragmentationPipelineStage.cs:79] Unity.Networking.Transport.FragmentationPipelineStage.Send
4. 0x00007FFF23C50359 (lib_burst_generated) a2fea2e3b114f5fd136a9e7079c2fa6d_x64_sse2
5. 0x00007FFF23C6EB5A (lib_burst_generated) a2fea2e3b114f5fd136a9e7079c2fa6d
6. 0x000000403718234F (Mono JIT Code) (wrapper managed-to-native) object:wrapper_native_00007FFF23C6EB50 (Unity.Networking.Transport.NetworkPipelineContext&,Unity.Networking.Transport.InboundSendBuffer&,Unity.Networking.Transport.NetworkPipelineStage/Requests&)
7. 0x000000403716BACA (Mono JIT Code) [C:\BuildAgent\work\69a805ec5677a170\Library\PackageCache\com.unity.transport@0.6.0-preview.7\Runtime\NetworkPipeline.cs:505] Unity.Networking.Transport.NetworkPipelineProcessor/Concurrent:ProcessSendStage (int,int,int,Unity.Networking.Transport.NetworkPipelineProcessor/PipelineImpl,Unity.Collections.NativeList`1<int>&,Unity.Networking.Transport.NetworkPipelineContext&,Unity.Networking.Transport.InboundSendBuffer&,Unity.Networking.Transport.NetworkPipelineStage/Requests&)
8. 0x000000403716AE83 (Mono JIT Code) [C:\BuildAgent\work\69a805ec5677a170\Library\PackageCache\com.unity.transport@0.6.0-preview.7\Runtime\NetworkPipeline.cs:383] Unity.Networking.Transport.NetworkPipelineProcessor/Concurrent:ProcessPipelineSend (Unity.Networking.Transport.NetworkDriver/Concurrent,int,Unity.Networking.Transport.NetworkPipeline,Unity.Networking.Transport.NetworkConnection,Unity.Networking.Transport.NetworkInterfaceSendHandle,int,Unity.Collections.NativeList`1<Unity.Networking.Transport.NetworkPipelineProcessor/UpdatePipeline>)
9. 0x000000403716A303 (Mono JIT Code) [C:\BuildAgent\work\69a805ec5677a170\Library\PackageCache\com.unity.transport@0.6.0-preview.7\Runtime\NetworkPipeline.cs:295] Unity.Networking.Transport.NetworkPipelineProcessor/Concurrent:Send (Unity.Networking.Transport.NetworkDriver/Concurrent,Unity.Networking.Transport.NetworkPipeline,Unity.Networking.Transport.NetworkConnection,Unity.Networking.Transport.NetworkInterfaceSendHandle,int)
10. 0x0000004037169AC3 (Mono JIT Code) [C:\BuildAgent\work\69a805ec5677a170\Library\PackageCache\com.unity.transport@0.6.0-preview.7\Runtime\NetworkDriver.cs:259] Unity.Networking.Transport.NetworkDriver/Concurrent:EndSend (Unity.Networking.Transport.DataStreamWriter)
11. 0x0000004037169533 (Mono JIT Code) [C:\BuildAgent\work\69a805ec5677a170\Library\PackageCache\com.unity.transport@0.6.0-preview.7\Runtime\NetworkDriver.cs:974] Unity.Networking.Transport.NetworkDriver:EndSend (Unity.Networking.Transport.DataStreamWriter)
12. 0x0000004037167713 (Mono JIT Code) [C:\BuildAgent\work\69a805ec5677a170\Packages\com.hugecalf.netcode\Runtime\NetPacketHandler.cs:382] hugecalf.netcode.NetPacketHandler:WriteBytesToDriver (bool,hugecalf.netcode.NetConn,int,System.Type)
13. 0x0000004037197A73 (Mono JIT Code) [C:\BuildAgent\work\69a805ec5677a170\Packages\com.hugecalf.netcode\Runtime\ServerNetPacketHandler.cs:40] hugecalf.netcode.ServerNetPacketHandler:SendToAll (hugecalf.IByteReadable)
14. 0x00000040371513C3 (Mono JIT Code) [C:\BuildAgent\work\69a805ec5677a170\Assets\Scripts\net\server\addons\XXXXXXGameServerAddOn.cs:209] net.server.addons.XXXXXXGameServerAddOn:FixedUpdate ()
15. 0x0000004013D5DA80 (Mono JIT Code) (wrapper runtime-invoke) object:runtime_invoke_void__this__ (object,intptr,intptr,intptr)
16. 0x00007FFF2130DB10 (mono-2.0-bdwgc) mono_get_runtime_build_info
17. 0x00007FFF21292902 (mono-2.0-bdwgc) mono_perfcounters_init
18. 0x00007FFF2129B95F (mono-2.0-bdwgc) mono_runtime_invoke
19. 0x00007FFF136D487D (UnityPlayer) scripting_method_invoke
20. 0x00007FFF136D14BC (UnityPlayer) ScriptingInvocation::Invoke
21. 0x00007FFF136B4AA3 (UnityPlayer) MonoBehaviour::CallMethodIfAvailable
22. 0x00007FFF136B4B88 (UnityPlayer) MonoBehaviour::CallUpdateMethod
23. 0x00007FFF13059050 (UnityPlayer) BaseBehaviourManager::CommonUpdate<FixedBehaviourManager>
24. 0x00007FFF1305FC9D (UnityPlayer) FixedBehaviourManager::Update
25. 0x00007FFF13305554 (UnityPlayer) `InitPlayerLoopCallbacks'::`2'::FixedUpdateScriptRunBehaviourFixedUpdateRegistrator::Forward
26. 0x00007FFF132F48BC (UnityPlayer) ExecutePlayerLoop
27. 0x00007FFF132F4987 (UnityPlayer) ExecutePlayerLoop
28. 0x00007FFF132F9224 (UnityPlayer) PlayerLoop
29. 0x00007FFF12DAA87B (UnityPlayer) PerformMainLoop
30. 0x00007FFF12DA948A (UnityPlayer) MainMessageLoop
31. 0x00007FFF12DAD996 (UnityPlayer) UnityMainImpl
32. 0x00007FFF12DAECCB (UnityPlayer) UnityMain
33. 0x00007FF66A6211F2 (XXXX) __scrt_common_main_seh
34. 0x00007FFF2D2813F2 (KERNEL32) BaseThreadInitThunk
35. 0x00007FFF2D9854F4 (ntdll) RtlUserThreadStart
36.  
37. ========== END OF STACKTRACE ===========

 

Thanks for the quick reply and the info, that all makes sense.

For the crash - I will try to create a minimal repro project and upload it.

Cheers,
Andy

 

@timjohansson I have been able to reliably reproduce the crash. It would seem that when sending packets of length 1386, 1387 or 1388 there is a problem with the fragmentation stage.

In the editor: if burst is enabled, sending packets of these lengths will throw an exception. If burst is disabled, Unity crashes.
In a build: the player crashes.

I have made a project and reported with the bug report tool (1313547)

Cheers,
Andy