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Comment by justinsaccount | Hacker News Reader

oooh, can we talk about the broken BSD utils on OS X next?

  $ du -hs big.log
  199M	big.log
  $ cat big.log | time tr 'a' 'b' | md5
         27.22 real        23.70 user         0.43 sys
  c171314106134f6fde035b11f4354464
  $ cat big.log | time gtr 'a' 'b' | md5
          1.05 real         0.30 user         0.23 sys
  c171314106134f6fde035b11f4354464

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Yes GNU spends a lot of time improving performance. A couple of examples from the most recent release, which you might think were too simple to optimize significantly:

The yes command (which is generally useful for generating repetitive text):

    $ yes-old | pv > /dev/null ^C
    ... 55.8MiB/s ...
    $ yes-new | pv > /dev/null ^C
    ... 3.44GiB/s ...

Details on that fairly simple change are at http://git.sv.gnu.org/gitweb/?p=coreutils.git;a=commitdiff;h...

Also we more than doubled the speed of wc -l (by avoiding function call overhead):

    $ yes | pv | wc-old -l ^C
    ... 230MiB/s ...
    $ yes | pv | wc-new -l ^C
    ... 558MiB/s ...

Also we now generate an infinite stream of integers more efficiently too:

    $ seq-old inf | pv > /dev/null ^C
    ... 13.3MiB/s ...
    $ seq-new inf | pv > /dev/null ^C
    ... 497MiB/s ...

Nice!

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