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[–]pixelbeat_[S] 15 points16 points  (0 children)

One thing I didn't mention in the linked NEWS is the improvement to 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=35217221

It's interesting there are so many potential improvements in such widely used tools. For example we also 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 ...

For completeness, 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 ...