Bug Using IJobEntity.Run() or IJobChunk.Run() triggers SafetyCheck. Bug?

I personally prefer using IJobEntity over the idiomatic foreach, as I find it to be more readable/maintainable. However, when I use .Run(), which I expected would run the job in place on the main thread, I get safety system related exceptions from jobs that write to queried components. Using .Schedule() gets rid of the problem, but then I'm paying the price of scheduling.

Here's an example derived from the Netcode samples, but using IJobEntity (this behavior is not exclusive to Netcode):

Code (CSharp):

1.     [WorldSystemFilter(WorldSystemFilterFlags.ServerSimulation)]
2.     [UpdateInGroup(typeof(InitializationSystemGroup), OrderFirst = true)]
3.     [BurstCompile]
4.     [RequireMatchingQueriesForUpdate]
5.     public partial struct GoInGameServerSystem : ISystem
6.     {
7.         public void OnCreate(ref SystemState state)
8.         {
9.         }
10.  
11.         public void OnDestroy(ref SystemState state)
12.         {
13.         }
14.  
15.         [BurstCompile]
16.         public void OnUpdate(ref SystemState state)
17.         {
18.             new ProcessGoInGameRpcJob
19.             {
20.                 Ecb = SystemAPI.GetSingleton<EndInitializationEntityCommandBufferSystem.Singleton>()
21.                     .CreateCommandBuffer(state.WorldUnmanaged)
22.             }.Run();
23.         }
24.  
25.         [WithAll(typeof(GoInGameRequest))]
26.         partial struct ProcessGoInGameRpcJob : IJobEntity
27.         {
28.             public EntityCommandBuffer Ecb;
29.  
30.             public void Execute(Entity rpcEntity, in ReceiveRpcCommandRequestComponent rpc)
31.             {
32.                 var connectionEntity = rpc.SourceConnection;
33.                 Ecb.AddComponent<NetworkStreamInGame>(connectionEntity);
34.                 Ecb.DestroyEntity(rpcEntity);
35.             }
36.         }
37.     }

Which gives the following exception, from WarnAboutStaleRpcSystem, which writes to one of the queried components:




Is that a bug, or is the alternative I'm looking for not supported? If it's the latter, what is the purpose of Run() given that it breaks with such a simple use case?

 

You should complete previous type dependency chain you want to read from main thread, as it's scheduled somewhere before and can write at any time and if you at the same time will try to read from the same memory (component) on main thread - it will be pure race condition from which safety system is protects you.

With burst compiled ISystem OnUpdate - that cost is neglectable

 

With Entities.ForEach().Run(), Dependency is automatically completed. However, I don't think that is the case with IJobEntity.Run().

 

Thanks, and turns out the codegen for the idiomatic for each complete dependencies as well, I missed that the first time I looked. Thanks for the clarification @eizenhorn and @DreamingImLatios