Progressively worse stuttering from UR counter with very high note count maps

[longnguyen2004]

Type

Performance

Bug description

Observed this while playing casually. Towards the end of the map, every note hit causes a very noticeable stuttering

Reproduction step:

• Play https://osu.ppy.sh/beatmapsets/1956376#mania/4094064 on Auto
• Seek to near the end of the map
• Add the UR counter. Observes that each note hit will result in a spike on the Update frametime graph
• Remove the UR counter. Observes that the spikes are gone (the remaining spikes seem to be GC related and can be ignored)

Screenshots or videos

ur.counter.stutter.mp4

Version

2024.1009.1

Logs

1731660081.network.log
1731660081.performance.log
1731660081.runtime.log
1731660081.auth.log
1731660081.input.log

[smoogipoo]

There's two issues here:

The raw performance of the method itself is pretty bad. A lot of time is spent checking types:

This could be fixed by something like this: https://gist.github.com/smoogipoo/fda9c73371309a2a581c726a12bceeb9, which I'd say is something we can apply with little thought.

That change will already make it somewhat reasonable for one displayed combo counter. The rest is because it's running over every single HitEvent every judgement, once per counter. Perhaps this could be improved by storing incremental data locally or via ScoreProcessor, but there comes the question of handling rewind (maybe you don't and static calculation?).

Leaving this here for now as I'm reprioritising, for if anyone else wants to take the lead.