Operating system: Windows 10
Graphics card: Nvidia 1060
all current 2.8 versions
Short description of error
Strangely poor performance when adding, editing and deleting subdivision modifier. On objects with 15+ booleans, it takes like 15 seconds to add 1 iteration of smoothing. On scenes with 4M+ faces, subdividing a simple sphere takes ages. Performance was excellent in 2.79b
Exact steps for others to reproduce the error
Create spheres with subdivision surfaces and duplicate until around 4M faces. Enjoy poor mesh mode performance.
Create an object with around 20 boolean modifiers. Add a subdivision modifier.