100% cpu usage in lightdm

[Yves-Alexis Perez]

Hey,

it seems that there's an issue with 0.9.4 cpu usage. It doesn't look like it's a resurgence of #770725 since it appears as soon as lightdm is launched, not after login.

Strac'ing the process doesn't give anything. If you need anything more, please ask.

[Yves-Alexis Perez (corsac)]

Note that it /seems/ fixed in bzr HEAD, not sure where the fix lies though.

[Robert Ancell (robert-ancell)]

Only the logs or a gdb trace would be useful here. Will keep an eye out for it (I haven't seen this).

[Yves-Alexis Perez (corsac)]

I've managed to run strace -f -p 1610 (lightdm pid):

[pid 1629] poll([{fd=10, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 3, -1) = 1 ([{fd=13, revents=POLLHUP}])
[pid 1629] poll([{fd=10, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 3, -1) = 1 ([{fd=13, revents=POLLHUP}])
[pid 1629] poll([{fd=10, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 3, -1) = 1 ([{fd=13, revents=POLLHUP}])
[pid 1629] poll([{fd=10, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 3, -1) = 1 ([{fd=13, revents=POLLHUP}])
[pid 1629] poll([{fd=10, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 3, -1) = 1 ([{fd=13, revents=POLLHUP}])
[pid 1629] poll([{fd=10, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 3, -1) = 1 ([{fd=13, revents=POLLHUP}])
[pid 1629] poll([{fd=10, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 3, -1) = 1 ([{fd=13, revents=POLLHUP}])
[pid 1629] poll([{fd=10, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 3, -1) = 1 ([{fd=13, revents=POLLHUP}])
[pid 1629] poll([{fd=10, events=POLLIN}, {fd=9, events=POLLIN}, {fd=13, events=POLLIN}], 3, -1) = 1 ([{fd=13, revents=POLLHUP}])

so it's one of the thread. I've looked at the patch between 0.9.4 and bzr head (I really can't use bzr so I can't do some kind of bisect) and it seems that the consolekit patches makes the bug disappear.

[papukaija (papukaija)]

This bug is confirmed in the duplicate report.

[whoop (tiredandnumb)]

This bug is still present in lightdm 0.9.5-0ubuntu1 (latest version)...

[whoop (tiredandnumb)]

This bug is still present in lightdm 0.9.7-0ubuntu1 (latest version)...

[Yves-Alexis Perez (corsac)]

Then it's a different bug, please open a new one.

[whoop (tiredandnumb)]

For me the cpu problem was gone in version: lightdm 1.0.0-0ubuntu2.
lightdm 1.0.0-0ubuntu2 was the only version where I did not have cpu usage maxed out.

But now the problem is back in version lightdm 1.0.0-0ubuntu3 (latest version)

[Yves-Alexis Perez (corsac)]

Indeed the problem seems back in 1.0.0

[Sebastien Bacher (seb128)]

Robert, does those comment which state that it was working when you broke the dbus wrapper are useful there?

[Yves-Alexis Perez (corsac)]

Note that this patch is not present upstream nor in the Debian package, where I can reproduce it consistently.

[Yves-Alexis Perez (corsac)]

Still present in 1.0.1

[Robert Ancell (robert-ancell)]

I saw this when disabling AccountsService, and it appears to be fixed by the change in bug 866035. Could you please confirm if you can still reproduce this?

[Yves-Alexis Perez (corsac)]

Seems indeed fixed again in 1.0.2

[whoop (tiredandnumb)]

I still suffer from the bug....

[whoop (tiredandnumb)]

Note I am not running 1.0.2 as there is no ubuntu package for that (yet)... The current ubuntu version for oneiric still has maxed out cpu problem.

@Robert Ancell: I am running version 1.0.1-0ubuntu4 and the accountsservice package has always been present on my systems, so bug 866035 does not seem to be related for me...

[whoop (tiredandnumb)]

Still a problem in 1.0.1-0ubuntu6

[Graham Poulter (graham-poulter)]

High CPU usage by lightdm 1.0.1-ubuntu6 on Ubuntu 11.10 64-bit.

[Viser (viser-m)]

Same on Ubuntu 11.10 32-bit(lightdm 1.0.1-ubuntu6)

[Sparhawk (sparhawkthesecond)]

Still there with lightdm 1.0.6 on Ubuntu 11.10 64-bit.

[cboettig (cboettig)]

I am still experiencing this problem in Ubuntu 12.10

[Sergi (sergi-fua)]

I've just started experiencing this problem in Ubuntu 12.04 LTS. Once I log in, lightdm uses 100% of a CPU.

[Dion (t-dion)]

Seeing this issue too, on fully updated 12.04.5 LTS.

To temporarily resolve (spinning fan on laptop is driving me crazy) revert back to lightdm/liblightdm 1.2.3-0ubuntu2.5 and restart.
(Synaptic: for both packages, select package, then menu Package->Force Version. Afterwards, select both packages then Package->Lock Version)

[Mael THOMINET (lau6chpad-net)]

Hi all,
I experience same problem on Ubuntu 12.04.5 LTS with lightdm 1.2.3-0ubuntu2.6
Regards,

[Matifou (matthieu-stigler)]

Hi

Same problem, resurged recently! With Ubuntu Ubuntu 12.04.5 LTS and 1.2.3-0ubuntu2.6 lightdm.

Thanks,

[Le Botlan (q-launchpad-lebotlan)]

Hi, I also confirm this bug on Ubuntu 12.04.5 LTS, after the latest update : lightdm constantly uses 100% CPU just after login.
Forcing the downgrade to lightdm 1.2.3-0ubuntu2.5 fixed this.

[Lucius Noctis Dacre (moon9river)]

Same issue here too, Ubuntu 12.04.5 LTS and 1.2.3-0ubuntu2.6 lightdm
Thank you

[Tassos (tas-sos)]

And I , from yesterday, after the weekly updates, by opening today my system (Ubuntu 12.04.5 LTS) i faced than same problem. One of my eight cores of my system worked at 100% .

As I watched from the application ''top'' the process charged my system was the "ightdm".

Than he shown from the application "synaptic package manager", i have installed the ''ightdm (1.2.3-0ubuntu2.6)'' version, description : http://pastebin.com/M6DKpJrV

Following this guide : http://www.g-lts.info/index.php/forum/odigoi-odigies-xrisis/247-ypovathmisi-paketon-se-proigoymeni-ekdosi
reverted to version "ightdm (1.2.3-0ubuntu2.5)" and longer everything move smoothly (as before).

If there is anything new please let as know.

Thank you very very mych. :)

(Sorry for the perhaps bad english)

[maarts (maarts)]

Same problem here.

Ubuntu Ubuntu 12.04.5 LTS and 1.2.3-0ubuntu2.6 lightdm.

[Eric van der Vlist (vdv)]

Same problem for me (Ubuntu 12.04.5 LTS and 1.2.3-0ubuntu2.6 lightdm)

[Robert Ancell (robert-ancell)]

The 1.2.3-0ubuntu2.6 SRU seems to have exposed this bug (see bug 1431654). Please check when 1.2.3-0ubuntu2.7 is released if this fixes the problem.

[Robert Ancell (robert-ancell)]

Closing this bug as it is so old. Please open a new bug if you are still getting issues like this.

[Falak (ubuntuoptimist)]

This reappeared in Ubuntu 16.04 LTS. Attached Screenshot.