Low smoke performance
See why smoke eats bunch of cpu time, specifically when you step into the smoke.
This also happens if you step in the smoke produced by the bullet impacts (eg. gibbing the player with smg). Or in the flames.
This happens if smoke polygons fill massive amount of the screen, for instance, staring at it through binoculars from the distance will cause frame drops.
Frames are also dropping in vet, but not as dramatic as in etl.
Issue seems to be related to renderer.