Bug 290017

Summary: kmix is pegging the cpu
Product: [Applications] kmix Reporter: mgolden
Component: generalAssignee: Christian Esken <esken>
Status: RESOLVED DUPLICATE    
Severity: normal CC: ddrs, EvilTwin1, smc+kdebugs
Priority: NOR    
Version: unspecified   
Target Milestone: ---   
Platform: Unlisted Binaries   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:

Description mgolden 2011-12-28 16:02:33 UTC
Version:           unspecified (using Devel) 
OS:                Linux

I have upgraded to the kubuntu 4.7.95 (4.8 RC1) beta.  For about the last 10 minutes, kmix was pegging the cpu.  It would not respond to keyboard events (to raise or lower volume), nor would it open from the launcher.

After about 10 minutes the problem resolved itself.

This appears to be new to the 4.7.95 packages as I have never seen this before

Reproducible: Didn't try

Steps to Reproduce:
I was playing some flash movies from my hard drive in vlc

Actual Results:  
kde process at 100%.  Unresponsive to keys or menu clicks

Expected Results:  
low cpu usage.
Comment 1 mgolden 2011-12-28 16:44:59 UTC
This has happened several times now.  It does not start when vlc starts, vlc has been playing for a while and then I notice the issue.  I will see if I can get this to happen with nothing playing.
Comment 2 mgolden 2011-12-28 18:12:08 UTC
OK, I started amarok instead of vlc and it pegged again.
Comment 3 mgolden 2011-12-28 20:38:58 UTC
I have watched this happen several more times, and it always seems to happen in amarok when one song ends and the next begins.  It never seems to happen in the middle of a song, nor if nothing is playing.

More info:

The backend is the phonon GStreamer backend 4.5.1 (at least according to amarok).

I should say that the machine is a System 76 Gazelle with a nVidia graphics/audio card, and there are two sound devices.  I am inclined to say that there is no problem with any of that, as
Comment 4 mgolden 2011-12-28 21:31:33 UTC
(oops - hit submit too soon.)

... as everything is working fine when kmix is not running.
Comment 5 Darryl 2011-12-29 01:18:01 UTC
This kmix excessive cpu usage is affecting my system too. I'm running Kubuntu 11.10 KDE 4.8 RC1 (4.7.95). It will use 100% of one cpu, since I'm using AMD triple core it is 33% per user who has used audio such as Clementine, kaffeine, audacious. Today 66% of my total cpu was being used by kmix alone. Hopefully this makes sense to someone.
Comment 6 S Clark 2011-12-29 04:47:04 UTC
Same here, for the last several iterations of 4.8beta/rc.  I can "kill -HUP" the kmix process and everything goes back to normal.  I can even then restart kmix and (for a while) it's normal.  Then eventually it happens again.

Perhaps something pulseaudio related?  As best I can tell, it does trigger when something starts (or perhaps stops) playing sound.  Flash plugin showing videos from youtube (from within firefox) is one situation where I've run into this, but not the only one.
Comment 7 Jean Luc 2011-12-29 18:13:13 UTC
happens here on chakra kde-unstable too (4.8 RC + PA + Phonon-Gstreamer)
Comment 8 Christian Esken 2011-12-30 17:00:39 UTC

*** This bug has been marked as a duplicate of bug 288675 ***