24 Sep
2022
24 Sep
'22
5:44 p.m.
On Sep 23, 2022, at 11:50 PM, Ali via cctalk
<cctalk(a)classiccmp.org> wrote:
I always thought the i960 was an upgrade to the i860 (sort of like i386 to i486 upgrade).
However, based on the info on wiki it seems as if the i960 actually came first and
although a RISC chip it was in no way in the same league as the i860. Anyone can clarify
or verify this?
I have very bad memories of the i960 from my time at Chipcom. The main memory I have is
that it uses an utterly misdesigned queue based I/O architecture, full of race conditions.
I think it's the same "design" used in the much maligned i82586 Ethernet
chip.
The odd thing is that others had done correct and race-free queue designs a decade or two
earlier, but Intel never showed any sign of design competence and it is just an example of
this that they screwed up I/O queues so badly.
paul