my $B = ...;           # bucket size
my @items = qw[ ... ]; # items
my @bins;
my @binsizes;

ITEM:
for my $item (sort { $b <=> $a } @items) {
   for my $bin (0 .. $#binsizes) {
      if ($binsizes[$bin] + $item <= $B) {
          push @{ $bins[$bin] }, $item;
          $binsizes[$bin] += $item;
          next ITEM;
      }
   }
   push @bins, [$item];
   push @binsizes, $item;
}

print "[@$_]\n" for @bins;