2017-11-17 8:14 GMT+01:00 Eli Zaretskii <eliz@gnu.org>:

> > From: Richard Copley <rcopley@gmail.com>
> > Date: Thu, 16 Nov 2017 20:45:36 +0000
> > Cc: Eli Zaretskii <eliz@gnu.org>, Jostein Kjønigsen <
> jostein@secure.kjonigsen.net>,
> >       Emacs developers <emacs-devel@gnu.org>, Jostein Kjønigsen <
> jostein@kjonigsen.net>,
> >       Drew Adams <drew.adams@oracle.com>, Phillip Lord <
> phillip.lord@russet.org.uk>
> >
> > Windows is ridiculously slow to start a new process.
>
> You mean Cygwin and MSYS, not Windows itself, right?  Because 99.99%
> of process starting during the build is MSYS Bash starting GCC, Grep,
> Find, and other programs.
>

Actually, it is the CreateProcess() call which is overkill for most of its
usages.
From what I have read, the problem comes from attaching default console,
checking permissions and stuff like that, which fork() does in a very
different way.
Windows has been designed for dlls and inter-dlls calls, not for processes
communicating
the way Unix did.