Hardware races

From: Bill Pechter <pechter_at_bg-tc-ppp892.monmouth.com>
Date: Tue Sep 18 09:16:13 2001

> Something tells me you'll be disappointed if you expect a PDP-whatever to keep
> up with a 486-66. If you stop and think about it, it's the rate at which a CPU
> gets in and out of memory that determines how fast it performs, and the memory
> for which the PDP-series processors were designed was quite a bit different from
> what was commonly used with a 486DX2.
>
> Dick
>

The PDP11/34 was more in line with the 286/12 or 16 for speed than the 486/66.
A 486/66 should be able to emulate an 11/70 at pretty close to the
11/70 speed...

IIRC an 11/780 was 1 VUPS and 11/750 was about .6 VUPS and 11/730
was about .3 VUPS. The 11/34A was about the same speed as the 11/73O
IIRC.

I seem to think UNIX on my 486/66 dhrystoned faster than the 8650 VAX
which seems to lead me to think the emulation should run close to, if
not faster than the real 11/70.

John Wilson's E11 ran like lightening on an old 486/75 laptop I had
(which just died). I think you could get 11/34 speed out of a '386 box.

Bill
Received on Tue Sep 18 2001 - 09:16:13 BST