[net.micro] Micro instruction timings

mwm@Okc-Unix@sri-unix (10/22/82)

From: Mike Meyer <mwm@Okc-Unix>
I put the following table together about 8 months ago, mostly from the book
`16 bit microprocessors' previously mentioned on the list. I no longer have
access to a copy, and can't recheck the validity of the times on the list.
They all look roughly as I remember them, except I could have SWORN that the
68000 timings were for a 6MHz 68000. If someone out there who has a copy
of the book could check and let me (the list) know, I'd appreciate it.


The only thing on the list that didn't come from the book is the 11/70
(maybe 11/44). These came from the digital hardware manuals, and were
made assuming that there were NO cache hits. Digital claims 90+% cache
hits on the 70, so it should do significantly better than this table
would indicate.

	mike

			16-bit processor timings (usec)

	IBM(1)	IBM	LSI-11	PDP	PDP(2)	8086	z8000	68000	16032
	4953	4955		11/40	11/70	5MHz	4MHz	8MHz(3)	???
-------------------------------------------------------------------------------
Moves:
RR	4.2	1.1	3.5	0.9	0.3	0.4	0.75	0.5	0.3
Direct	8.0	3.08	7.0	3.2	 -	2.8	2.25	2.0	1.4
Index	8.6	3.3	7.7	2.92	2.25	3.4	2.5	1.5	1.0

Adds:
RR	4.2	1.1	3.5	1.0	0.3	0.6	1.0	0.5	 -
Direct	8.4	3.3	7.0	3.34	 -	3.0	3.0	3.0	 -
Index	9.0	3.52	7.7	3.06	2.4	3.6	3.25	2.5	1.5

Mult	27.6	16.9	67.15	10.62	6.0	30.0	17.5	8.75	4.4

Call	6.6	1.98	7.0	3.24	2.25	3.8	3.0	2.0	2.5

Jump	4.2	1.59	3.5	1.76	0.6	3.4	1.5	1.25	0.7
-------------------------------------------------------------------------------
RR - Register to Register	Index - using an index register
Mult - 16 bit multiply

(1) The two IBM processors are both Series 1's.
(2) Assuming no cache hits.
(3) I think this is actually 6MHz