yes per second を競う人々の話を思い出した
[base] Revision 319897
https://svnweb.freebsd.org/base?view=revision&revision=319897
> Improve yes' throughput
>
> On my system, this brings up the throughput from ~20 to ~600 MiB/s.
>
> Inspired by: https://www.reddit.com/r/unix/comments/6gxduc/how_is_gnu_yes_so_fast/