[Info-vax] What are the earliest DEC operating systems you worked with ?

[Bob Eager]

On Thu, 04 Mar 2021 19:05:53 +0000, Paul Hardy wrote:

> Jeffrey H. Coffield <jeffrey at digitalsynergyinc.com> wrote:
>> 
>> 
>> On 03/04/2021 10:28 AM, Arne Vajhøj wrote:
>>> On 3/4/2021 12:20 PM, Chris Townley wrote:
>>>> On 04/03/2021 16:50, Marc Van Dyck wrote:
>>>>> Simon Clubley laid this down on his screen :
>>>>>> What are the earliest DEC operating systems you worked with ?
>>> 
>>>>> University, 1980. VAX/VMS V2.0 on a VAX 780.
>>>>> 2,5 GB of memory, 3 disks of 72 MB each, a tape drive, and 40 serial
>>>>> lines hooked to VT100 or LA120 (for APL, we were FT site) terminals.
>>>>> Ah yes, and two LPxxx printers and a card reader.
>>>>> Never left VMS after that, till now...
>>> 
>>>> That was a vast amount of memory then!
>>>> 
>>>> We ran a full production setup with 80 odd users in 1990 with 32Mb
>>> 
>>> I strongly suspect that it was a typo.
>>> 
>>> I don't think you could stuff 2.5 GB in a 780 and at 1980 RAM prices
>>> it would be crazy expensive.
>>> 
>>> Arne
>>> 
>> Vax 11/780 max memory was 64MB.
>> 
>> Jeff
>> 
>> 
> The default for a 780 when launched was 1/4 MB (256K). When we got ours
> in 1979 I argued and got a further 1/2 MB to make 3/4 MB. It cost about
> a quarter of the company profit for the year! The boss said that as we
> were moving from a PDP-11 with 64KB, then 256 KB ought to be plenty!
> 
> Remember the V in VMS is virtual, and VMS pages were only 1/2 KB, so if
> you had 1 MB you had 2048 pages to act as a memory window to the
> disk-based page and swap areas.

Less 8kB (16 pages) for the page tables. And a few more! :)




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