Bigint speeds

bigint-timetrial.p6

use v6;

sub bigpackids(int @ids) {
  my $ret = 0;

  my $c = 0;
  while $c++ < +@ids  {
    $ret = $ret +| (1 +< (@ids[$c] - 1));
  }
  return $ret;
}

my int @a = ((^256).roll + 1) xx 256;
say "Starting: " ~ my $instant = now;

bigpackids(@a) xx 10_000;

say "Ran bigpackids 10,000 times (sequential): {now - $instant}";

$instant = now;

await do for ^4 {
    start {
        say "started in thread $_";
        bigpackids(@a) xx 2_500;
        say "finished in thread $_";
    }
}

say "Ran bigpackids 10,000 times (parallel): {now - $instant}";