Re: NetBSD truss(1), coredumper(1) and performance bottlenecks

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Fri, 24 May 2019 06:34:58 -0000 (UTC)
    From:        mlelstv%serpens.de@localhost (Michael van Elst)
    Message-ID:  <qc83ai$ded$1%serpens.de@localhost>

  | That's probably the shell that must read input byte by byte in most cases.

The shell actually very rarely does one byte reads when not reading
from the terminal (and even then only for command line editing).

That used to be important in the pre Bourne-shell days, but the time
of the shell passing the open script to child processes to read from
are long gone - and without that, it isn't as important that there
be no readahead.

Of course, if something is passing it one byte at a time through a pipe
(doing unbuffered writes to a pipe) then anything is possible.

kre