Tony Duell wrote:
However, 'What is an instruction?'. I've
heard it said that the 11/780
averaged 500,000 of its machine instructions per second, but that that
was about as much processing as 10^6 of other machine's instructions
The VAX-11/780 cranked out about as many Dhrystones as an
IBM System/370 158 which did (apparently) chew through about
one million instructions per second.
Quite how the VAX-11/780 became the reference 1 MIP machine
while technically cranking through only half that many instructions
is something that I've never figured out. Anyone know?
Oddly enough, even IBM accepts this history:
http://www-306.ibm.com/chips/techlib/techlib.nsf/techdocs/BFDAA658D08935
5987256B3E0075E163/$file/Benchmarking.pdf
Antonio