Re: Fix for slow process output processing (please test).

[David Kastrup <dak@gnu.org>]

"Eli Zaretskii" <eliz@elta.co.il> writes:

> > From: David Kastrup <dak@gnu.org>
> > Date: 05 Jan 2004 16:57:14 +0100
> > > 
> > > I suppose that process-adaptive-read-buffering isn't really needed
> > > on Windows,
> > 
> > Since Windows is slow, anyway?
> 
> I think the reason is that Windows never feeds Emacs with such small
> chunks from a pipe.
> 
> > I suppose the problem could be that the Windows equivalent of
> > "select" that Emacs uses does a busy wait without yielding the
> > CPU.
> 
> I think that's not true: it does yield the CPU.  See
> w32proc.c:sys_select.

More exactly: my guess is that the equivalent may yield the CPU to
the operating system, but the operating system may be of the opinion
that it will prefer to use up short delay slots by an active wait
rather than letting other processes run.  In short: it is my
suspicion that the yielded CPU time does not arrive at the intended
place.  You could not know this from Emacs sources, however.  We'd
need somebody with Windows insights to get more of a clue.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum