Subject: bug#34618: closed (Re: bug#34618: 26.1.92; timerfd interface causes slowdown on Cygwin)

From: [email-masked] (GNU bug Tracking System)
Date: Fri, 22 Feb 2019 16:16:02 +0000

Your bug report

#34618: 26.1.92; timerfd interface causes slowdown on Cygwin

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
34618: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=34618
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#34618: 26.1.92; timerfd interface causes slowdown on Cygwin
From: Ken Brown <[email-masked]>
Cc: "[email-masked]" <[email-masked]>
Date: Fri, 22 Feb 2019 16:15:18 +0000
List-Id: <debbugs-submit.debbugs.gnu.org>

Closing.

Subject: 26.1.92; timerfd interface causes slowdown on Cygwin
From: Ken Brown <[email-masked]>
To: "[email-masked]" <[email-masked]>
Date: Fri, 22 Feb 2019 15:08:33 +0000
List-Id: <debbugs-submit.debbugs.gnu.org>

Starting with cygwin-3.0.0, Cygwin has the timerfd functions.  But using
them causes Emacs to be very slow to respond to user input.  If I press
a key, there is a 1-2 second delay before Emacs responds.  I'm in the
process of trying to debug this
(http://www.cygwin.org/ml/cygwin/2019-02/msg00364.html).  In the
meantime, the attached patch disables the use of these functions.

OK for the emacs-26 branch (after filling in the bug number)?

Ken
From c0025015ac30ae3c61388eb98f39f495926fe5d1 Mon Sep 17 00:00:00 2001
From: Ken Brown <[email-masked]>
Date: Fri, 22 Feb 2019 09:53:52 -0500
Subject: [PATCH] Disable the timerfd interface on Cygwin

* configure.ac (emacs_cv_have_timerfd): Set to "no" on Cygwin.
---
 configure.ac | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/configure.ac b/configure.ac
index d5e802a961..0783b6455a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -4145,6 +4145,10 @@ AC_DEFUN
 AC_SUBST(TERMCAP_OBJ)
 
 # GNU/Linux-specific timer functions.
+# Bug #?????.
+if test "$opsys" = "cygwin"; then
+  emacs_cv_have_timerfd=no
+fi
 AC_CACHE_CHECK([for timerfd interface], [emacs_cv_have_timerfd],
   [AC_COMPILE_IFELSE(
      [AC_LANG_PROGRAM([[#include <sys/timerfd.h>
-- 
2.17.0