The Roact scheduler (SchedulerHostConfig) always uses 15ms of frametime even when running higher than 60 FPS

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I would write this as a Feature Request but A: I haven’t requested access yet, and B: I’m not sure which category fits best.

Time and time again there’s been countless reports about this one source of random frame drops on Roblox, the dreaded SchedulerHostConfig.default. (#3321673, #3883265)
The two linked bug reports have recent updates and both images show a similar thing to what I experienced which drove me to write this, this new “App” label randomly being executed, causing frame drops. Instead of having to report all these new lag sources that randomly pop up, maybe there’s a solution to better hide the activity?

So if I’m not mistaken SchedulerHostConfig.default is related to Roact, hence why the bug report title.
The library itself is fine, in fact it’s great that it has a scheduler that chooses to split up the work it needs to do across multiple frames to avoid lag spikes. The problem I have with this is how much work it decides to do every frame, approximately 15ms. So I wonder:

Keeping the question really simple, is it possible to change the amount of runtime that Roact targets for per-frame activity to follow the user’s target framerate?
This isn’t a foolproof solution to eliminating framerate impact, but if someone’s playing at a clean 240FPS then a runtime of 4ms while still impacting the final framerate, would be WAY less damaging than a runtime of 15ms which would normally drop you down to 60 FPS or below.
If these issues of random lag caused by internal functions outside of a developer’s control are going to keep popping up, this would at least make them less damaging to the user experience.

If this isn’t possible, I’d still like to bring up the newest lag source that made me write this bug report in the first place, which has also been seen by others:
microprofile-20250924-200220.html (5.5 MB)

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I’m fairly sure this is the same issue:

I would read through it because it mentions a lot of important details.

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That seems like it yes, and it is in fact mentioning a similar workaround that I’ve found as well.
The lag is avoided by joining games directly from the website, and will only start happening if you ever leave a game into the Roblox App.

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Salutations!

Thanks for reporting this.
It seems from the replies that this is a duplicate of the topic above.

That topic was already assigned for investigation.
I’ll have to close this one as a duplicate, but feel free to reach out if you have any additional insights on the active thread:

Thanks for your patience and your understanding.
Have a nice day!

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