bug#20927: 24.5; Cygwin Emacs completely blocks for 5+ seconds

[Eli Zaretskii <eliz@gnu.org>]

> From: Sebastien Vauban <sva-news@mygooglest.com>
> Date: Mon, 29 Jun 2015 15:21:27 +0200
> 
> 1. Starting Cygwin Emacs,
> 2. Opening whichever local file (`org-mode/lisp/org.el', in my case),
>    and
> 3. Keeping constantly our index on the Down arrow key to make the buffer
>    scroll indefinitely,
> 
> Emacs blocks (after 30 seconds scroll or so) for 5 entire seconds, and
> then revives...
> 
> I've tracked down this problem in Cygwin Emacs, and it's due to this
> line:
> 
> --8<---------------cut here---------------start------------->8---
>   (global-auto-revert-mode 1)           ; Auto refresh buffers.
> --8<---------------cut here---------------end--------------->8---
> 
> When it's commented, Cygwin Emacs behaves normally.

Probably because you use glib's notifications, and they seem to
suck...

What happens if you set auto-revert-use-notify to nil before turning
on global-auto-revert-mode?

(Btw, I think global-auto-revert-mode is evil, and advise not to use
it.  Especially with file notifications.  Just turn on
auto-revert-mode in those buffers/mode hooks where you really need
that.)