Re: segmented mem - Re: Debian Server Compromise -- A Fire Drill ??
On Sat, 06 Dec 2003 16:54:39 -0800, Alvin Oga wrote:
> On Sat, 6 Dec 2003, Paul Morgan wrote:
>> IBM did popularize the term "PC", but they sure as heck didn't invent the
>> personal computer. And, because they'd bought the rights to the Intel
>> 8086, and because of the sheer economic power and brand recognition of
>> IBM, we all got stuck with the dreadful Intel segmented memory
> my understanding is that segmented mem like the x86 makes it easy
> for context swap and page fault recovery ??
> - 68000 and Z8000 has a harder time to do "recovery"
> but easier to write code and faster for general aps
> i like pdp-style apps ... everything directly accessible as memory ...
> c ya
> - google just had a party at the computer museum ..
> - computer museum happen to have all these old toys
> ( pdp-8, cray-1, ... all working ...
> ( paper tape, catridges, punch cards too
Segmented memory addressing is cheaper, don't need as wide an address bus,
and it certainly adds a level of complexity to asm programming, and of
course it's slower. I didn't do any asm programming after the 8086/8088,
but there was no hardware memory management as you suggest until the
80386. The big downside of that is that all memory was available to all
processes; all you had to do was just not play by the OS's rules.
I'm digging back in my memory for this, so please read IIRC for every
"The number of UNIX installations has grown to 10, with more expected."
(The UNIX Programmer's Manual, 2nd Edition, June 1972)