[Info-vax] OpenVMS.Org quick pool

[David Froble]

Jan-Erik Soderholm wrote:
> David Froble wrote 2012-08-18 22:22:

>> That then would raise the question, which hardware is "easiest", 
>> "fastest",
>> "best" to emulate ?

Note that the question is just about emulation of hardware.  Not talking about 
software.

>> I'd be highly surprised if there is any software running on VMS on IA-64
>> for which there is no sources.  The painful lessons were first learned
>> going from VAX to Alpha.  If there is, well, the "hindmost" is usually 
>> the
>> first to get caught.
>>
>> Other than speed, how many users really needed Alpha?  Ok, availability
>> too.  I wonder what percentage of those still using VMS actually need the
>> capabilities of Alpha.
> 
> That is, still using VMS *today* that needed Alpha *then* ?
> Or that could run their VMS operations on VAX *today* ??
> 
> I guess most "still using VMS" today are larger operations.
> 
> And didn't most of us saw the benefits? Faster and larger memories.
> Noone needed larger memory than VAX supported? Well, maybe not from
> day one of Alpha, but a bit later and in particular *today*?

This gets away from the question.  If any emulation is running on an x86, where 
CPU and memory and all else is the same, then the question that I posed is which 
HW could be "easiest, best, fastest" emulated.

>> There is also those things implemented on Alpha,
>> but never implemented on VAX.  Even so, that is software, not hardware.
>>
>> A good question is, "is an emulated Alpha surperior to an emulated VAX?",
>> all else being equal?  I'd be interested to know.
> 
> Yes, since Alpha's run later versions of VMS (and Rdb) then VAX does.
> That's enough for me.

Again, that's software, not hardware.

As an exercise, suppose that your options are emulated VAX, and emulated Alpha, 
and the emulated VAX gave better performance than the emulated ALpha.  Without 
getting into software versions, which would you prefer.

That would of course raise the question of how hard would it be to get VMS V8.4 
running on VAX, which I doubt would be feasible because of the 64 bit stuff.

But the question I was asking was, which HW would perform best in emulation on 
x86?  I think it is an interesting question.

> Jan-Erik.
>