Carlos Murillo skrev:
At 03:43 PM 11/9/01 -0500, Dave wrote:
>On November 9, Iggy Drougge wrote:
>> Isn't this rather odd? The MicroVAX II is supposed to be 0,5 VUP, right?
>> So what have the DEC engineers done to make it just as fast in the
>>Dhrystone and
>> even faster than the 11/780 in the Whetstone benchmarks?
>
> 0.9 VUP, not 0.5.
Didn't the uVax II implement some of the original
VAX instructions
with emulation? I always wondered what the VUP rating would have
been were they not emulated.
According to "Great Microprocessors of the Past and Present (V 12.1.2)":
Further inspiration came from the MicroVAX (VAX 78032) implementation, since
in order to reduce the architecture to a single (integer) chip, only 175 of
the 304 instructions (and 6 of 14 native data types) were implemented (through
microcode), while the rest were emulated - this subset included 98% of
instructions in a typical program. The optional FPU implemented 70
instructions and 3 VAX data types, which was another 1.7% of VAX instructions.
All remaining VAX instructions were only used 0.2% of the time, and this
allowed MicroVAX designs to eventually exceed the speed of full VAX
implementations, before being replaced by the Alpha architecture.
Mind you, the original MicroVAX was only 0,3 VUP (I really hope I'm right this
time =).
I wonder if that qualifies as the slowest machine to run NetBSD. On further
inspection, NetBSD doesn't mention any MicroVAX I support. Still, 0,9 VUP is
quite little. One competitor might be the 010-based Sun 2s (a new port).
Some time ago, someone on thist list used the phrase "though not as slow as a
PC523". Is the PC532 really that slow?
--
En ligne avec Thor 2.6a.
Amiga 4000/040 25MHz/64MB/20GB RetinaBLTZ3/VLab/FastlaneZ3/Ariadne/Toccata