System Information
Operating system: Darwin-19.0.0-x86_64-i386-64bit 64 Bits
Graphics card: Intel Iris OpenGL Engine Intel Inc. 4.1 INTEL-14.2.16
Blender Version
Broken: version: 2.81 (sub 16), branch: master, commit date: 2019-11-15, hash: rBc25a910e4ec0
Short description of error
I can't draw by any brush without lag if I open 2.8 files with different sculpted models. Lag is noticeable after the first undo after a brush stroke.
Lagging may be incredibly huge and sculpting in 2.8 in comparison with 2.81 is like jet. If I'm trying to sculpt from scratch something in 2.81, it seems to have no problems like these.
My models from 2.8 are high-poly so this is the reason maybe.
Exact steps for others to reproduce the error
Open high poly mesh in sculpt mode (few million polygons), make one stroke and then undo. Lag is noticeable.
[Developer note: it may only work in 2.8 specific files, still pending file from reporter]