[TUHS] PDP-11 legacy, C, and modern architectures

[Larry McVoy]

On Thu, Jun 28, 2018 at 04:39:58PM +0100, Tim Bradshaw wrote:
> > On 28 Jun 2018, at 15:58, Larry McVoy <lm at mcvoy.com> wrote:
> > 
> > You completely missed my point, I never said I was in favor of single
> > cpu systems, I said I the speed of a single cpu to be fast no matter
> > how many of them I get.  The opposite of wimpy.
>
> And this also misses the point, I think.  Defining a core as 'wimpy'
> or not is dependent on when you make the definition: the Cray-1 was not
> wimpy when it was built, but it is now.

That's not what I, or Ted, or the Market was saying.  We were not comparing
yesterday's cpu against todays.  We were saying that at any given moment,
a faster processor is better than more processors that are slower.

That's not an absolute, obviously.  If I am running AWS and I get 10x
the total CPU processing speed at the same power budget, yeah, that's
interesting.

But for people who care about performance, and there are a lot of them,
more but slower is less desirable than less but faster.  There too much
stuff that hasn't been (or can't be) parallelized (and I'll note here
that I'm the guy that built the first clustered server at Sun, I can
argue the parallel case just fine).

People still care about performance and always will.  Yeah, for your
laptop or whatever you could probably use what you have for the next
10 years and be fine.   But when you are doing real work, sorting
the genome, machine learning, whatever, performance is a thing and
lots of wimpy cpus are not.