A day playing with the flip fluids // whitewater solver.
Very impressed with the VBD meshing stuff in Houdini 12.5....
I can't remember the exact particle counts... but times all though hbatch (as memory usage in particular during the meshing was extremely high ~ 19gb) were about;
sim 4 hours
mesh 6 hours
White Water 4 hours
Render (surface , foam, spray @ 720p) 6 hours