[racket-dev] Fwd: [shootout-Feature Requests][312552] Scheme PLT should be renamed to Racket

From: Robby Findler (robby at eecs.northwestern.edu)
Date: Sun Jun 20 12:26:51 EDT 2010

Matthew has just pushed a commit that may have fixed the strange
behavior described below.


On Fri, Jun 18, 2010 at 10:41 AM, Vincent St-Amour <stamourv at ccs.neu.edu> wrote:
> At Fri, 18 Jun 2010 10:05:57 -0500,
> Robby Findler wrote:
>> Perhaps it suggests a bug in the interaction between that fancy
>> require operator and the optimizer?
> Actually, the benchmark on the shootout webpage is named
> mandelbrot-unsafe.rkt in the repository. The version I had in mind is
> mandelbrot.rkt, which does use fl+ without renaming it.
> After running mandelbrot-unsafe.rkt 50 times, it does show some
> variance in the running times (it runs for between 7 and 10 seconds,
> with times following what looks like a normal distribution), but much
> less than mandelbrot.rkt (between 19 and 40 seconds, with times
> following a bimodal distribution, with peaks around 20 and 40). The
> small variation for mandelbrot-unsafe.rkt (combined with the fact that
> times are distributed normally) indicates that it's probably noise. On
> the other hand, the bimodal distribution observed on mandelbrot.rkt is
> probably a sign that something weird is going on.
> The slowdown observed on the shootout webpage, since it's based on
> mandelbrot-unsafe.rkt, could thus be caused by the upgrade to 5.0. The
> running time inconsistencies due to fl+ and co is likely a separate
> issue.
> Vincent

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