Operating system: Windows-10-10.0.18362 64 Bits
Graphics card: GeForce RTX 2080 Ti/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 431.60
CPU : Intel i9-9900K
Broken: version: 2.81 (sub 14), branch: master, commit date: 2019-10-07 20:16, hash: rBa856c5eccffb
Short description of error
When working with multiple particle emitters on a same object, The Bake All Dynamics button doesn't bake anything (when the particles are hair). I had the problem with 2.80 and checked with 2.81 if this was addressed but apparently not.
It is not very efficient to have to go through every particle system in the scene and bake them individually.
Especially since baking individually will only use one CPU core.
Perhaps a solution could be to start launching individual blender instances for every particle system ? This way it would make use of multiple cores. It is sad to see my cpu maxing out at 12% when baking a hair sim, while the other 7 cores are sitting idle…
If for some technical reason All Hair Dynamics cannot be baked with a single click, maybe gray out the Bake All Dynamics Button while in "hair" mode ? It would save a lot of people some time searching why this doesn't work...
Exact steps for others to reproduce the error
Just add a particle system, switch to hair instead of emitter, and Bake All Dynamics will do nothing.