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

[Ken Brown <kbrown@cornell.edu>]

On 6/29/2015 9:21 AM, Sebastien Vauban wrote:
> Hello,
>
> When:
>
> 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 can't reproduce this on my system.  I held my finger on the down arrow 
for about 2 minutes.

> 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.
>
> Note the above line does NOT cause any trouble in Windows Emacs...

One difference is that Cygwin Emacs uses gfilenotify, based on GLib.  I 
recall a discussion some time ago (either on emacs-devel or in a bug 
report) about problems with gfilenotify, but I don't remember if the 
problems were resolved.

Ken