ubuntu-location-serviced uses 100% CPU

[Olivier Tilloy]

On build #100.
After playing with geolocation in the browser (browsing to maps.google.com) a few times, I found out that the location service daemon is using 100% CPU all the time:

top - 09:06:49 up 24 min, 1 user, load average: 1.15, 2.10, 2.45
Tasks: 184 total, 1 running, 183 sleeping, 0 stopped, 0 zombie
%Cpu(s): 12.9 us, 41.0 sy, 0.0 ni, 46.1 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
KiB Mem: 710104 total, 537912 used, 172192 free, 2196 buffers
KiB Swap: 524284 total, 23208 used, 501076 free, 236516 cached

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
  527 root 20 0 103m 5200 4180 S 99.7 0.7 15:15.13 ubuntu-location
 2482 root 20 0 8840 832 324 S 3.0 0.1 0:55.90 systemd-udevd
  725 root 20 0 8844 1244 744 S 2.0 0.2 0:40.96 systemd-udevd
 6245 root 20 0 2352 1100 740 R 1.0 0.2 0:00.07 top
   78 root 20 0 0 0 0 S 0.3 0.0 0:02.17 kworker/u:2
  642 root 20 0 380 92 72 S 0.3 0.0 0:05.03 ueventd
  718 root 20 0 2092 808 496 S 0.3 0.1 0:09.65 upstart-udev-br
 1360 phablet 9 -11 104m 2880 1752 S 0.3 0.4 0:10.75 pulseaudio
 1389 phablet 20 0 438m 107m 69m S 0.3 15.5 0:38.28 unity8
    1 root 20 0 3276 2036 1008 S 0.0 0.3 0:04.02 init
    2 root 20 0 0 0 0 S 0.0 0.0 0:00.01 kthreadd
    3 root 20 0 0 0 0 S 0.0 0.0 0:00.06 ksoftirqd/0
    6 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/0
    7 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/1
    8 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kworker/1:0
    9 root 20 0 0 0 0 S 0.0 0.0 0:00.07 ksoftirqd/1

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: ubuntu-location-service-bin 0.0.2+13.10.20131016.1-0ubuntu1
Uname: Linux 3.0.0-3-maguro armv7l
ApportVersion: 2.12.5-0ubuntu2
Architecture: armhf
Date: Thu Oct 17 09:08:32 2013
InstallationDate: Installed on 2013-10-17 (0 days ago)
InstallationMedia: Ubuntu 13.10 - armhf (20131017)
MarkForUpload: True
SourcePackage: location-service
UpgradeStatus: No upgrade log present (probably fresh install)

[Olivier Tilloy (osomon)]

I’m not seeing any crash file for the location service, however the browser did crash in the course of my tests.

[Olivier Tilloy (osomon)]

After killing the daemon process, it is respawned automatically by upstart, and it’s back to a normal CPU usage (0% when idle).

[Olivier Tilloy (osomon)]

Output of strace on the daemon when it’s consuming 100% CPU:

    root@ubuntu-phablet:/# strace -p `pidof ubuntu-location-serviced`
    Process 6619 attached
    futex(0x453ff4c8, FUTEX_WAIT, 6633, NULL

[Olivier Tilloy (osomon)]

Attaching the stacktrace obtained by attaching gdb to the running daemon. Not very useful.

[Olivier Tilloy (osomon)]

The attached branch (lp:~thomas-voss/location-service/fix-1240878) doesn’t fix the CPU usage. I’ve installed the packages built from the branch, rebooted, and I’m still able to reproduce the issue.

[Launchpad Janitor (janitor)]

This bug was fixed in the package location-service - 0.0.2+14.04.20140204-0ubuntu1

---------------
location-service (0.0.2+14.04.20140204-0ubuntu1) trusty; urgency=low

  [ thomas-voss ]
  * * Fix a race when a session is created while another one ends. *
    Ensure a sensible minimum interval between consecutive location
    updates in the GPS provider. (LP: #1240878)
  * Adjust to changes in new dbus-cpp version.
 -- Ubuntu daily release <email address hidden> Tue, 04 Feb 2014 12:36:02 +0000

[Launchpad Janitor (janitor)]

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

[Rolf Leggewie (r0lf)]

saucy has seen the end of its life and is no longer receiving any updates. Marking the saucy task for this ticket as "Won't Fix".