[rescue] Wanted: Old Sun Hardware

[Carl R. Friend]

    On Wed, 14 Oct 2009, nate at portents.com wrote:

> [... I]n-order vs. out-of-order is a very arbitrary way to
> rank processors, which was my point, though that arbitrariness
> almost works for just Sun hardware...

    In-order versus out-of-order might well be considered the
borderline between "classic" architectures/implementations
and so-called "modern" ones.  Once one gets into the out-
of-order dispatch of instructions the human that's ultimately
doing the programming turns everything over to faith in the
compiler and the chip-set.  At the point where the behaviour
of a program may be non-deterministic based on the whim of
the CPU, detailed tracing and troubleshooting -- indeed
"provability" -- becomes if not impossible, then impractical.

    Certainly, the modern crop of CPUs are not machine-language
programmable by humans and even if they were (given the vagaries
of OOO execution) they're not particularly troubleshootable.
I have a vague inkling that we may be looking at the "God question"
here -- at what point do we, as humans, turn over our last rational
thought to "faith" that the machine will actually do precisely
what we tell it to?

    Please feel free to call me a throwback, but I actually like it
when I can describe what a system is actually doing when it executes
a program I have written.  This is best done at the gate level.

+------------------------------------------------+---------------------+
| Carl Richard Friend (UNIX Sysadmin)            | West Boylston       |
| Minicomputer Collector / Enthusiast            | Massachusetts, USA  |
| mailto:crfriend at rcn.com                        +---------------------+
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