Warning: Stalled gamethread waiting for particles

Hello we’re having this warning spammed alot in our packaged build. It happend when we’re turning particle systems on and off, which we do rather often by calling DeactivateSystem on ParticleSystemComponents from C++.

Mostly this stall is in tens of thousands fractures of ms, according to log, but it spams this a lot of times, making log close to unusable.

As I understand the source of this is WaitForAsyncAndFinalize which is just spinning in main thread waiting for AsyncWork to complete.

What are we doing wrong and what is the correct way of disabling emitter, if not by using Deactivate/DeactivateSystem in particle system component?

Thank you.

I did some more researching, and found out that guys from Unreal Tournament had same problem: https://unrealtournament.atlassian.net/browse/UT-3932.

That is how they fixed it: https://github.com/EpicGames/UnrealTournament/commit/e6953e642c9b2da87ac510bd0c3b46e7901c822f

We probably will switch to same fix for now, but would be nice to get some official comments in case we’re missusing particle systems in some way and can fix warning without rebuilding the engine.

I also have this problem- tagging in case you get a response.

I like how the fix is turning off the log spam :smiley:

Any updates on this?

I,m having the same issue with a parameterized burning effect driven by a termprature parameter.

The effect itself is sober but eveytime it starts it spams these warnings.

That fix on Github Dldls posted says not found?

How did they fix it?

I cant see that solution it says not found?

How did they fix it?

I cant see that solution it says not found?

Not sure i can post code here, you need to be registered in epicgames github where unreal engine sources are.

They switched UE_LOG macro from Warning to Verbose so it do not spam. Not sure that it’s official fix though. And you need to recompile engine after that.

We also have this on iOS but it causes awful long stalls in millisecond range.