it's an issue with smh - playback currently works in a crap way, it is possible to make it better addon-way though it's going to take a while until that would be ready.

you could somewhat improve the playback performance by removing keyframes from modifiers you don't use, by separating them on different timeline and shift selecting keyframes on it (select first and last keyframes with shift held down to select them and all frames inbetween) and deleting them, though probs with 2k frames it may not help too greatly. having "always freeze" turned on or whatever also helps.

引用自 PenolAkushari：

it's an issue with smh - playback currently works in a crap way, it is possible to make it better addon-way though it's going to take a while until that would be ready.

you could somewhat improve the playback performance by removing keyframes from modifiers you don't use, by separating them on different timeline and shift selecting keyframes on it (select first and last keyframes with shift held down to select them and all frames inbetween) and deleting them, though probs with 2k frames it may not help too greatly. having "always freeze" turned on or whatever also helps.

Thanks a lot!