Summary
5.8: Big physics update performance regression
Hi,
We’re seeing a large performance regression in physics updates in the editor, and possibly in-game as well, though we haven’t checked yet.
After clearing instances on large instance components, on the next tick, ChaosPushData takes 30x longer to finish.
This causes some of our larger procedural map generation processes to take multiple minutes instead of just seconds.
What Type of Bug are you experiencing?
Simulation
Steps to Reproduce
You can find the repro project here: https://drive.google.com/file/d/1Dx1QukXz7XfTwDsYvc04yJHWjDRZ1EFN/view?usp=sharing.
Open ReproMap, select PCGVolume, and run Cleanup in the Details panel.
Here are the recorded traces:
UE 5.8: https://drive.google.com/file/d/1Li6KRo9_C0Jps0vCWvdjbFmjpBp5OMLj/view?usp=drive_link
For comparison, the same operation in UE 5.7: https://drive.google.com/file/d/1df6Nyf55r0pJFHPEWy3Vkr4ZbE2wR1de/view?usp=drive_link
Expected Result
Physics updating fast.
Observed Result
Slow update. Regression from previous engine version.
Affects Versions
5.8
Platform(s)
Windows
