[GTALUG] example of why RISC was a good idea

[Lennart Sorensen]

On Sun, May 22, 2016 at 12:11:13AM -0400, D. Hugh Redelmeier wrote:
> | From: Alvin Starr <alvin at netvel.net>
> | I believe the last original CPU design from intel was the iAPX 432.
> 
> i860? i960 (with Siemens)? Itanium (with HP)?

I think it depends if you consider those designs "original".

> Yeah.  It kind of pulled an Intel.  The AMD architecture filled a
> growing gap in x86's capability and was good enough.

Well unlike intel they did actually clean up a bit while extending
the size.

> One of Intel's motivations for Itanium seemed to be to own the
> architecture.  It really was unhappy with having given a processor
> license to AMD.

Well if they hadn't done that, then IBM would almost certainly not have
used them in the PC.  So instead they would probably have gone with
the M68k.  Too bad for us intel did license it.

> I didn't mention MIPS.  Mostly because they seem to be shrinking.
> Most MIPS processors that I see are in routers and newer models seem
> to be going to ARM.

I guess you haven't seen the Cavium Octeon chips then.

> If I remember correctly, some Alpha folks went to AMD, some went to
> Sun, and some went to Intel.
> 
> Intel doesn't have all the good ideas even if it had all the processor sales.

We can thank the Alpha team for hyperthreading, QPI (and hypertransport),
and a number of other goodies.

> AMD's first generation of 64-bit processors was clearly superior to
> Intel's processors, up until the Core 2 came out.  AMD still
> lost to Intel in the market.  It's sad to see AMD's stale products now.

The netburst architecture was a stupid move by intel.  They assumed they
could increase clock rates to 10GHz+ and designed an architecture that
required doing that.

> I think that ARM's good idea was to stay out of Intel's field of view
> until they grew strong.  Intel had an ARM license (transferred from
> DEC) from the StrongARM work.  They decided to stop using it after
> producing some chips focused on networking etc. ("XScale").  They sold
> it to Marvell.

Actually they still have it.  They some some of it to Marvell.  Intel sold
the PXA line (application processors) but kept the IXP and IOP line
(network and I/O processors).  Of course these days intel also owns
Altera which is putting arm cores in FPGAs.

> There were and are a lot of architectures in the embedded space but
> ARM seems to be the one that scaled.  It could be the wisdom of ARM
> Inc. but I don't know that.

Or just a bit of dumb luck.  They did seem to realize that making
computers and chips was the wrong market to be in and that selling
designs and licenses was a much better business plan.  The initial
design was as far as I know just a case of seeing a CPU design house,
reading an IBM white paper on RISC, and deciding "Well we can do that too"
and then doing it.

-- 
Len Sorensen