Deadlock UE4.15 when using pak games

Question

Hi,

We've just switch to UE4.15 and in a dev packaged build using pak files we have a deadlock coming from the wwise plugin integration.

 

This is what I can see:

in CAkUnrealIOHookDeferred::Read the wwise critical section is locked. in the same function we start a read request in IORequestHandle->ReadRequest which will then lock the cache critical section. On a secon thread we receive a a read complete callback which will lock the cache crtical section and call the lambda... which want a lock on wwise critical section.

And here is the dead lock.

Has anyone seen that? Any fix on the way?

 Edit: actually it looks like the issue is also happening with the other operation such as close or cancel with the same behavior.

Cheers

 

Olivier

Answer 1

Hi,

I think we have seen a similar issue. I have only paused when the engine has gone stalemate, and then it's waiting in SoundEngine::LoadBank on the main thread and in FPakPrecacher::QueueRequest on the thread IOSchedThread.

For us it was temporarily resolved by disabled the new "Event Driven Loader" that comes enabled with 4.15. You can find this in Settings > Project Settings > Streaming > Event Driven Loader Enabled and uncheck that checkbox

I hope this helps you in the wait for 2016.2.4

Cheers,
Markus