Xfce Forum

billsmugs

Member

Registered: 2015-02-26

Posts: 4

Xfwm4 freezing when opening certain applications

If I try to open certain applications (currently only seems to be the Atom text editor and the Genymotion Android emulator), xfwm4 uses 100% of one CPU core and the GUI (including all windows and panels, but not the mouse cursor) freezes for at least ~10-15 mins before the application opens, after which it seems to work OK and the CPU usage goes back to normal. All other programs that I've tried so far can start up properly, but there might be others that cause the issue that I haven't tried.

If I switch to a terminal with Ctrl+Alt+F1 while it's crashed, login and run 'sudo service lightdm restart' (instead of waiting around for the program to eventually open), when I log in xfwm4 will still be using 100% of one core for a bit, before settling down again to normal levels.

If I use a different window manager (e.g. metacity) the programs start up as normal, but if I run 'metacity --replace' while it's using high CPU (after restarting lightdm), the xfwm4 process hangs around as before.

I'm using Xubuntu 14.10 and this problem has only started recently (although I'm not sure exactly when, as I haven't wanted to use either of the problem applications for a couple of weeks). 'xfwm4 -V' reports "This is xfwm4 version 4.11.2 (revision cfa3c47) for Xfce 4.10"

Any ideas what might be causing this? Is it worth upgrading to xfce 4.12, as described here: http://ubuntuportal.com/2015/03/how-to- … 14-10.html to fix the problem, or will that possibly cause other problems (as it uses the xubuntu-dev ppa)?

ToZ

Administrator

From: Canada

Registered: 2011-06-02

Posts: 11,494

Re: Xfwm4 freezing when opening certain applications

Not sure I have an answer, but maybe some info to help you identify the cause:

1. I can't remember the exact Xubuntu versions where the log files changed, but do a tail on either:

tail -f ~/.xsession-errors

...and/or

tail -f ~/.cache/upstart/startxfce4.log

...while trying to start up those apps to see if you can catch exact error messages that might help point you in the right direction.

2. Is there anything common (libraries, platforms) between the apps that are exhibiting this problem? Unfortunately, I am not familiar with either of them.

---

Please remember to mark your thread [SOLVED] to make it easier for others to find
--- How To Ask For Help | FAQ | Developer Wiki  |  Community | Contribute ---

billsmugs

Member

Registered: 2015-02-26

Posts: 4

Re: Xfwm4 freezing when opening certain applications

.xsession-errors didn't have anything and the only (possible?) items of interest in startxfce4.log were a few lines saying:

(nm-applet:3318): GLib-GObject-WARNING **: /build/buildd/glib2.0-2.42.1/./gobject/gsignal.c:3101: signal id '193' is invalid for instance '0x1a1b650'

But I had an idea and after playing around with window manager themes I've sorted the problem, though I'm still not sure why it happened.

I'm using custom window decorations that basically remove the controls and just have a thin outline on active windows (see screenshot here, the right hand window is active, the left hand one is inactive). The .xpm files in the xfwm4 theme folder are just single-colour square images, either grey or transparent. If the images are 1x1, 2x2, 4x4, 6x6, 7x7 etc pixels in size then it works fine, if they are 3x3 or 5x5 the the problem occurs (just for the two programs mentioned).

I believe Atom uses elements of Chromium and is written in javascript, but I can use Google Chrome without any trouble with the 3x3 borders and I don't know about Genymotion (although it does integrate/interface with Virtualbox in some way, which also works fine with the 3x3 borders).