Re: New ISA board to play with transputers

On 07 Jul 2025 17:21:11 +0100 (BST), Theo
<theom+news@chiark.greenend.org.uk> wrote:

john larkin <jl@glen--canyon.com> wrote:

 
Seems a shame to have an x86 core wasting time handling ethernet and
printers and mice and memory sticks when they could be doing better
things like running Spice.

>
Many of those things are already happening outboard anyway - all those
things have processors in them.  What the CPU is doing is largely managing
the data transfer to and from the device.  eg the printer speaks PCL or
Postscript and the OS's workload is limited to firing the job at the printer
(USB/network) and the printer's CPU then decides where to put the ink on
the page.
>
You can delegate that management oversight to another core if you like, but
then you need management oversight of *that* core.
>

My Windows 11 thing is running hundreds of processes right now. That's
crazy.

>
Windows problems :-)  But many of those things don't need to take much CPU -
they're ready to handle print jobs when you press Ctrl-P, but the rest of
the time they're ticking along in the background not taking much resources
because they don't need them.
>
The OS is running thousands of kernel threads, but they're mostly blocked
(not scheduled) until they need to do something.  One thread per 'thing',
more or less.  All that thread needs is a few hundred bytes for its register
state so the impact is small.
>

Computing is a mess. A new hardware architecture would at least
suggest a fresh start.

>
Non-Windows, non-x86 architectures are available...
>
Theo

The x86 is nearly the peak of the silly concept that the CPU is a big
deal. Intel is heavily invested in that idea. ARM and Risc-V cores are
fast and cheap and basically trivial amounts of silicon. We can have a
zillion CPUs on a chip so don't benefit from the brutal complexity and
inefficiency of trying to share just a few big ugly CPUs among
hundreds of processes.

We use the RP2040 chip in some products. It's a dual-core 133 MHz ARM
with lots of cute peripherials, including hardware state machines.
It's 75 cents in any quantity. On the new version, the RP2350, they
threw in a couple of RISC-V cores just for fun.