kded4 consumes 100% CPU

[Andrew Kohlsmith]

Fresh install of natty alpha 1 from USB, went through many package updates (never dist-upgrade, just upgrades). Logged in, used bluetooth tether to phone, disconnected, left for breakfast. Came back and kded4's stuck at 100% CPU. Not bluetooth related, as it has happened normal wifi or ethernet access. I am not 100% sure if it happens without any network access, but I think it may have something to do with an internet connection going away and coming back.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: kdelibs-bin 4:4.6.2-0ubuntu2
ProcVersionSignature: Ubuntu 2.6.38-7.39-generic 2.6.38
Uname: Linux 2.6.38-7-generic x86_64
Architecture: amd64
Date: Sat Apr 9 12:56:42 2011
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha amd64 (20110202)
ProcEnviron:
 SHELL=/bin/bash
 LANG=en_CA.UTF-8
 LANGUAGE=
SourcePackage: kde4libs
UpgradeStatus: No upgrade log present (probably fresh install)

[Sander van Grieken (sander-vangrieken)]

Same on i386 natty,

booting from USB HDD, seen with both FOSS nvidia video driver and binary driver.

[Kishore (kitts)]

Happens here too when i disconnect my Android phone using usb tethering. The device comes up as an ethernet device. When i disconnect USB kded4 shoots up to 100% CPU making the complete system mostly and plasma completely unusable. I have to kill kded4 (killall -9 kded4) and restart it.

It seems that kded4 cannot handle the disappearing network device. I have to try this to check if it even happens when i disconnect the regular ethernet cable.

It sure does not happen with wireless network going off. Not sure if it happens when the wireless device itself goes off!

[Roberto Oppedisano (roberto-oppedisano)]

Happens here too with both wifi and VPN connections. It seems related to appearing/disappearing of connections that use credentials.

[_djura_ (netking)]

I run 64-bit Kubuntu Natty. In System Activity I found 3 processes "knotify4". Two owned by root, and one by me. One of those two owned by root was taking up 50% of dual core processor. I killed that process and system activity was back to normal. I don't use wifi or VPN, but I tried to disconnect/reconnect ethernet cable, but nothing happened. Right now I have no idea what caused this earlier, but I will keep you posted if I come up with something new.

[Teemu Ollakka (teemu-ollakka)]

64-bit Kubuntu Natty. Killing pppd while having kded4 running makes kded4 go wild. Attached with gdb and got the stack trace in StackTrace.txt. Further inspection revealed that the process was stuck looping within frame #1.

[mero (merovirgian)]

Similar:
https://bugs.launchpad.net/ubuntu/+source/kde4libs/+bug/772183
https://bugs.launchpad.net/ubuntu/+source/kde4libs/+bug/768714
https://bugs.launchpad.net/ubuntu/+source/kde4libs/+bug/776567