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aguther avatar image
aguther asked aguther commented

Potential performance issue over time caused by lights


When the A32NX is running for some hours just standing on the runway (but also in flight as reported by users), the sim builds up a performance issue on the main thread that can be solved by turning off and on the NAV lights.

It does not happen with the default A320 as it seems, but it hints for an underlying issue in the game engine that is for sure worth solving.


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Hello @aguther

Sorry for the delay.
This issue will be investigated.
Thank you for reporting it :)


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If this is the case it may also explain the post SU9 performance issue we are seeing with some of our scenery as it makes a lot of use of lights.

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Hello @aguther

Some update on this. We've been able to reproduce the issue.
It seems to come from the particle system used for your lights, it ends up spawning way too many particles.
I don't know yet which fx is the culprit and if it's a problem of configuration that leads to infinite lifetime particle or an issue in the code.
I'll keep digging.


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1 Answer

FlyingRaccoon avatar image
FlyingRaccoon answered aguther commented

Hello @aguther

The problem has been identified.
Your LIGHT_A32NX_LogoLightAmbient.fx file defines an emitter with infinite lifetime, a rate of 1 particle / second, and it spawns particles that have infinite lifetime.
There was no protection against this in the old FX system code so you end up constantly spawning particles that never die.
Turning the light off was resetting the emitter and clearing all its particles.
You can fix this by setting a lifetime for your emitter or particles, just like you did in your other fx files.

We will enforce a maximum number of particles per emitter on our side to solve the problem.


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Wow and thank you so much for this investigation and sorry for causing this. We will change that on our side. The fix on your end might also in other cases where developers are (as we) not aware of it.


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