Kdeconnectd uses 100%

Status changed to 'Confirmed' because the bug affects multiple users.

Same here with

Package: 0.7.1-0ubuntu3
CurrentDesktop: KDE
DistroRelease: 14.10 utopic

I noted that this happens (at least to me) every time my smartphone disconnects from the wifi my laptop is connected to. If I get out of the wifi range, kdeconnect starts to eat my cpu, every time.

Package: 0.7.1-0ubuntu3
Kubuntu 14.10
Qt: 4.8.6
KDE: 4.14.1

When I run kdeconnectd from the terminal the error that appears before it uses all the CPU is:
"fusermount: entry for /home/matty/.kde/share/apps/kdeconnect/caed8a53d8d7bee7 not found in /etc/mtab"

kdeconnect 0.7.3-0ubuntu1~ubuntu14.04.1

strace reveals its stuck in infinite loop reading a dead resource

LLIN}])
[pid 7539] read(3, "\2\0\0\0\0\0\0\0", 16) = 8
[pid 7539] recvmsg(7, 0xbf819a24, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid 7539] write(3, "\1\0\0\0\0\0\0\0", 8) = 8
[pid 7539] write(3, "\1\0\0\0\0\0\0\0", 8) = 8
[pid 7539] clock_gettime(CLOCK_MONOTONIC, {1479222, 248670395}) = 0
[pid 7539] recvmsg(7, 0xbf819a04, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid 7539] poll([{fd=3, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}, {fd=15, events=POLLIN}, {fd=16, events=POLLIN}, {fd=5, events=POLLIN}, {fd=20, events=POLLIN}, {fd=21, events=POLLIN}, {fd=10, events=POLLIN}, {fd=51, events=POLLIN}, {fd=52, events=POLLIN}, {fd=8, events=POLLIN}, {fd=57, events=POLLIN}], 14, 0) = 1 ([{fd=3, revents=POLLIN}])
[pid 7539] read(3, "\2\0\0\0\0\0\0\0", 16) = 8
[pid 7539] recvmsg(7, 0xbf819a24, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid 7539] write(3, "\1\0\0\0\0\0\0\0", 8) = 8
[pid 7539] write(3, "\1\0\0\0\0\0\0\0", 8) = 8
[pid 7539] clock_gettime(CLOCK_MONOTONIC, {1479222, 249052541}) = 0
[pid 7539] recvmsg(7, 0xbf819a04, 0) = -1 EAGAIN (Resource temporarily unavailable)
[pid 7539] poll([{fd=3, events=POLLIN}, {fd=7, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}, {fd=15, events=POLLIN}, {fd=16, events=POLLIN}, {fd=5, events=POLLIN}, {fd=20, events=POLLIN}, {fd=21, events=POLLIN}, {fd=10, events=POLLIN}, {fd=51, events=POLLIN}, {fd=52, events=POLLIN}, {fd=8, events=POLLIN}, {fd=57, events=POLLIN}], 14, 0) = 1 ([{fd=3, revents=POLLIN}])

In addition to CPU, sometimes kdeconnectd will use upwards of 300 MiB of RSS:

USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
dotanco+ 1787 1.0 11.6 1055976 342448 ? Sl Nov19 172:14 /usr/lib/x86_64-linux-gnu/libexec/kdeconnectd

This is my system:

$ cat /etc/issue
Ubuntu 15.10 \n \l

$ uname -a
Linux loathe 4.2.0-17-generic #21-Ubuntu SMP Fri Oct 23 19:56:16 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

Operating System: Kubuntu 21.04
KDE Plasma Version: 5.21.3
KDE Frameworks Version: 5.80.0
Qt Version: 5.15.2
Kernel Version: 5.11.0-13-generic
OS Type: 64-bit
Graphics Platform: Wayland
Processors: 4 × Intel® Core™ i5-3337U CPU @ 1.80GHz
Memory: 3.7 GiB of RAM
Graphics Processor: Mesa DRI Intel® HD Graphics 4000

I searched on the Internet and found someone also reported on KDE bugtracking system.
Some KDE processes (like kdeconnectd) are not killed after session logout, hog CPU
https://bugs.kde.org/show_bug.cgi?id=433293
The workaround is to configure systemd to KillUserProcesses=yes in /etc/systemd/logind.conf. Although this is most definitely a bug.(https://www.reddit.com/r/kde/comments/lnscdt/kdeconnectd_hogs_cpu/)

I confirm same problem as qqydw (qydwhotmail)

Operating System: Kubuntu 21.04
KDE Plasma Version: 5.21.4
KDE Frameworks Version: 5.80.0
Qt Version: 5.15.2
Kernel Version: 5.11.0-16-generic
OS Type: 64-bit
Graphics Platform: X11
Processors: 3 × AMD Phenom(tm) 8650 Triple-Core Processor
Memory: 3.8 GiB of RAM
Graphics Processor: AMD RV730

kdeconnectd is using 100% of cpu (2 instances)
processor temperature reached and remained at 66 deg C
solved easily temporarily by kill -9 both instances
cpu temperature went down to 42 deg C and stable , cpu 10% after kill

apart from that, plasma 5.21.3 is great, I love it.

noticed this issue twice today on Kubuntu 22.04

from what i can tell this package is used for communicating with phones, this is not something i would bother using

no idea why this would be sitting there randomly eating 100% of 2 cores waiting on something to happen when i never tried to do anything with a phone

Operating System: Kubuntu 21.10
DE: KDE 5.86.0 / Plasma 5.22.5
see also bug/1922465

When a second user attempts to log out it appears to log out, but afterwards gradually the fans rise to full speed.

If the first user (never logged out just locked) logs back in and runs sudo htop you can see 60ish pids running in the name of the second user, 6ish of those are using 100% of all cores.

The pids that are hogging are xdg-desktop-portal-kde and at least one kdeconnectd, usually multiple threads of kdeconnectd.

Each of the threads that those pids are in are end with a drconqi pid that, if you kill it, the entire thread closes and that core frees up.

If all of the hogging threads are killed in that way that still leaves 50ish pids running in the name of the second user, but they use 0% CPU. I have been killing all of second users threads without noticing any repercussions.

Further testing shows it doesn't matter who does the logging out
Kdeconnectd processes get a drkonqi thread attached and max out the cpu, and so that user never gets fully logged out.

Has not happened to me using X11 when logging in.