[Info-vax] OT: obscure PDP11 OSes (even more dinosaury)

[David Froble]

Johnny Billquist wrote:
> On 2015-06-15 15:36, Simon Clubley wrote:
>> On 2015-06-15, Dirk Munk <munk at home.nl> wrote:
>>> bill at server3.cs.uofs.edu (Bill Gunshannon) wrote:
>>>>
>>>> Of course, all of this still doesn't explain how the VAX was
>>>> "a best-seller" when compared to the PDP-11 when the PDP-11
>>>> sold 50% more systems.
>>>>
>>>
>>> Because one VAX could do the work of several PDP-11's?
>>
>> In the early days of the VAX, wasn't there some literature floating
>> around showing how the PDP-11 was faster at some things than the VAX ?
>>
>> This was before my time however so I may be wrongly remembering
>> something I read in the past.
> 
> Interrupt response times on the PDP-11 are way better than on VAXen, 
> which led to people not wanting to downgrade from a PDP-11 to a VAX...
> 
>     Johnny
> 

Swapping can be rather detrimental to observed interrupt times ....

When your program is sitting in memory, because it can, things are 
usually better.

Ok, I'm not saying there weren't some things the PDP-11 did better, when 
it wasn't over burdened with more tasks than the memory could handle.