Some hacks I'll share!

[Kenneth Almquist]

Another way to clear memory fast on PDP-11 machines is to use the mov
instruction instead of the clear instruction.  The clr instruction
performs a read, modify, write sequence on all the PDP-11 machines that
I have looked at.  Reading from a register is faster than reading from
memory, so if you have a spare register you can zero it, and then replace
the clr instructions in the loop with moves from the register.
					Kenneth Almquist