Do some parallel prime finding in the most naive way.

parallel-primes.p6

#!/usr/bin/env perl6

use v6;
use Stats;

sub bench($name, &code) {

    my ($start,$end);
    my $max = 1000;
    my @times;

    for 1..100 {
        $start = now;
        code($max);
        $end = now;
        @times.push($end-$start);
    }
    my $sd = sd @times;
    my $mu = mean @times;
    say "$name: ran in $mu seconds (σ = $sd seconds)";
}

bench 'primes-parallel', {
    my @primes = (2 .. $^max).race(batch => $^max / 2, degree => 2).grep({
        (2 .. $^n - 1).race(batch => $^n / 2, degree => 2).grep($^n %% *).elems == 0;
    });
}

$ perl6 parallel-primes.p6
No exception handler located for catch
at src/gen/m-CORE.setting:677 (/Users/matt/.rakudobrew/moar-glr/install/share/perl6/runtime/CORE.setting.moarvm:THROW-NIL:6)
from src/gen/m-CORE.setting:732 (/Users/matt/.rakudobrew/moar-glr/install/share/perl6/runtime/CORE.setting.moarvm:next:12)
$ perl6 parallel-primes.p6
moar(2277,0x1138fc000) malloc: *** error for object 0x7fc0a8817688: incorrect checksum for freed object - object was probably modified after being freed.
*** set a breakpoint in malloc_error_break to debug
/Users/matt/.rakudobrew/bin/perl6: line 2: 2277 Abort trap: 6 PATH=/Users/matt/.rakudobrew/bin/../moar-glr/install/bin:$PATH perl6 "$@"