15 Oct
2012
15 Oct
'12
10:48 a.m.
On Oct 15, 2012, at 1:09 PM, Dave McGuire wrote:
On 10/15/2012 12:48 PM, Ethan Dicks wrote:
Those systems also all had virtual memory subsystems; the Mac and
the PC didn't have MMUs until the 68020 and 286, respectively (and
even then, the Apple/Motorola PMMU kind of sucked, and 286 Protected
Mode wasn't quite real MMU action). All that is not to say that
doing multitasking without paged MMUs in a small memory footprint
is impossible, since plenty of OSes did so, but it's a barrier to
the lazy programmer.
- Dave
As for multitasking OS, I'd have to trot out
the Amiga in 1985.
Completely derided as a "toy machine" by both the PC and Mac crowds,
again, from day one, multitasking OS. I can't find a reference to the
original quote, but sometime around 1985 or 1986, Steve Jobs and Bill
Gates were deflecting calls for each of their products to support
"true" multitasking (vs the existing "Switcher" or "TSR"
mechanisms
that let you push one app to the side to run another in the
foreground) with claims that you "couldn't do it" on a machine that
had less than 2MB (that being more than most people had in front of
them at the time). At the time, my interpretation was more along the
lines of "it's too hard to we
Had they never heard of S/360?! I know damn well they'd heard of
PDP-10 and PDP-11 systems...all of which were doing damn fine
multitasking with a fraction of 2MB.