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Re: one-line programs
mdj wrote:
On Feb 1, 12:12 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:
I remember typing in one example that rendered the Mandelbrot set in
hires, then waiting the 5-6 hours for it to render, just because of
found it ingenious :-)
A direct evaluation of the Mandelbrot set at hires takes about seven
hours whether it's a one-liner or not. ;-) I use it as a demonstration
of "embarrassing parallelism" for the AppleCrate--in fact, I used it at
KansasFest (though the demo was interrupted by my zapping it with ESD!).
Yikes! I hope the zap only interrupted the network or reset a host;
I'd not enjoy the job of replacing a shift register on slave 10 :-)
Nor would I! ;-)
The Apple II boards are remarkably robust, so all the transient did was
cause a wild branch into the weeds. A reboot restored it to health. ;-)
With 16 processors running it, and "jobs" assigned by line number, it
get linear speedup, and runs in about 26 minutes--so the plan was that
it would finish by around the middle of my talk. ;-)
Fun to watch it render too, I bet!
Yes, I first assigned the lines in order, so, even though they take
different lengths of time to compute, the result image tended to build
linearly from top to bottom. So I decided to shuffle the lines in the
work queue to cause the image to fill in random order--making the image
_gestalt_ pretty clear after less than half the lines have been
completed. There's a bit of drama as only a few lines remain, with a
sort of "horse race" to see which machines will finish first. ;-)
-michael
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