Try replacing your calculation of @sorted with a Schwartzian Transform, something like this:

my @sorted=
  map { $_->[0] }
  sort { $a->[1] cmp $b->[1] }
  map { [$_, ( / (\d*\.\d*) ms/ and $1 or 0 ) ] }
  @data;
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The part of the "expensive function" in merlyn's note is played by

/ (\d*\.\d*) ms/ and $1 or 0
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which just returns the first (and in this case only) thing that looks like a ping time in the current string. (Update: I should mention the "or 0" is to make sure any lines with no valid ping time sort to the bottom.)

IMPORTANT NOTE: GrandFather++ is right about my absent-mindedly using "cmp" instead of "<=>". It should have been

my @sorted=
  map { $_->[0] }
  sort { $a->[1] <=> $b->[1] }
  map { [$_, ( / (\d*\.\d*) ms/ and $1 or 0 ) ] }
  @data;
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