WHIPTHREAD
Type: Integer
Saved in: Registry
Initial value: 1
Controls whether to use an additional processor to improve the speed of operations such as ZOOM that redraw or regenerate the drawing.
WHIPTHREAD has no effect on single processor machines.
0 - No multithreaded processing; restricts regeneration and redraw processing to a single processor. This setting restores the behavior of AutoCAD 2000 and previous releases.
1 - Regeneration multithreaded processing only; regeneration processing is distributed across two processors on a multiprocessor machine.
2 - Redraw multithreaded processing only; redraw processing is distributed across two processors on a multiprocessor machine.
3 - Regeneration and redraw multithreaded processing; regeneration and redraw processing is distributed across two processors on a multiprocessor machine.
When multithreaded processing is used for redraw operations (value 2 or 3), the order of objects specified with the DRAWORDER command is not guaranteed to be preserved for display but is preserved for plotting.