[Info-vax] For sale: VAXstation 4000/90 128MB Fully Working and Tested

[Johnny Billquist]

On 2022-07-02 00:50, Bill Gunshannon wrote:
> On 7/1/22 16:02, Arne Vajhøj wrote:
>> On 7/1/2022 2:31 PM, Bill Gunshannon wrote:
>>> Was it?  My guess is that the only improvement that might have been
>>> needed for Dave's application was a faster processor.  And that was
>>> done even after the death of the PDP-11 in DEC's eyes.
>>
>> I don't think PDP-11 not being available was the driver behind the
>> move to VAX.
> 
> Not lack of availability at first, but complete stoppage of development
> played a major role.

There wasn't. Last release of RSX was in 1999.

>> PDP-11 production continue until 1997 when people were migrating
>> from VAX to Alpha - not to VAX.
> 
> How much development was done during that period?  How many shrinks
> to increase speed?  How many new peripherals were made available?
> We didn't even get decent network cards or even disk controllers for
> things like SCSI except from third parties.  Trust me, people using
> PDP-11's could see the writing on the wall.

There wasn't much demand for speed increase. But DEC even did offer 
their own SCSI controller (RQZX1), so it wasn't just third party. You 
are drawing conclusions from incorrect data.

The biggest reason for migration from PDP-11 to VAX was because of the 
larger virtual memory addressing space.

People really did not (in general) enjoy trying to squeeze ever larger 
software systems into the tiny addressing space. It was a lot of effort 
that could be spent elsewhere.

   Johnny