DB<109>  $w=""; $a="x" x 300; $t=time; $w.=$a for (1..200_000); print time-$t, ":", length $w
9:60000000
  DB<110> $x="x" x 60000000; $x=""; $a="x" x 300; $t=time; $x.=$a for (1..200_000); print time-$t, ":", length $x
0:60000000