cpu race between nautilus, hud- and unity-service

[Sam_]

Reproducable on guest and -user account. (on pc and laptop)
Seen on user account first.
Initial report from guest account (attached .xession-errors and screenshot of terminal output).
Open a terminal and run 'top' to view processes.
Open Nautilus, right click only on bookmarked folders and open properties.
Result: nautilus, unity-panel and -hud service race cpu.
Fan speed increases from ~1100 to ~2000 rpm (viewed on user account with conky).

Viewing properties of folders which aren't bookmarked doesn't result in cpu race.
The behaviour has been introduced since recent unity updates.

compiz-core:
  Installed: 1:0.9.7.2-0ubuntu1
  Candidate: 1:0.9.7.2-0ubuntu1
  Version table:
 *** 1:0.9.7.2-0ubuntu1 0

~$ lspci -nnk | grep -i VGA -A2
01:00.0 VGA compatible controller [0300]: Advanced Micro Devices [AMD] nee ATI RV710 [Radeon HD 4350] [1002:954f]
 Subsystem: PC Partner Limited Device [174b:174b]
 Kernel driver in use: radeon

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: unity 5.8.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-20.32-generic 3.2.12
Uname: Linux 3.2.0-20-generic x86_64
ApportVersion: 1.95-0ubuntu1
Architecture: amd64
CompizPlugins: [core,composite,opengl,compiztoolbox,decor,vpswitch,snap,mousepoll,resize,place,move,wall,grid,regex,imgpng,session,gnomecompat,animation,fade,unitymtgrabhandles,workarounds,scale,expo,ezoom,unityshell]
Date: Mon Mar 26 18:33:32 2012
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20120204)
ProcEnviron:
 TERM=xterm
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: unity
UpgradeStatus: No upgrade log present (probably fresh install)

[Bilal Akhtar (bilalakhtar)]

That's really weird, and I managed to reproduce it too. Can't understand how this is related to Unity, but I guess it's related to the appmenu exported by the properties dialog. Not sure though.

[Sam_ (and-sam)]

Still reproducable with latest updates.
unity:
  Installed: 5.8.0-0ubuntu2
  Candidate: 5.8.0-0ubuntu2
  Version table:
 *** 5.8.0-0ubuntu2 0
        500 http://archive.ubuntu.com/ubuntu/ precise/main amd64 Packages
        100 /var/lib/dpkg/status

compiz-core:
  Installed: 1:0.9.7.2-0ubuntu4
  Candidate: 1:0.9.7.2-0ubuntu4
  Version table:
 *** 1:0.9.7.2-0ubuntu4 0
        500 http://archive.ubuntu.com/ubuntu/ precise/main amd64 Packages
        100 /var/lib/dpkg/status

indicator-appmenu:
  Installed: 0.3.95-0ubuntu2
  Candidate: 0.3.95-0ubuntu2
  Version table:
 *** 0.3.95-0ubuntu2 0
        500 http://archive.ubuntu.com/ubuntu/ precise/main amd64 Packages
        100 /var/lib/dpkg/status

[Sam_ (and-sam)]

Race still exists but decreased significant with latest update compared to #3.
indicator-appmenu:
  Installed: 0.3.96-0ubuntu2
  Candidate: 0.3.96-0ubuntu2
  Version table:
 *** 0.3.96-0ubuntu2 0
        500 http://archive.ubuntu.com/ubuntu/ precise/main amd64 Packages
        100 /var/lib/dpkg/status

[Sam_ (and-sam)]

No decrease on laptop with latest update. Leaving properties open for a while results in cpu fan running forever.
indicator-appmenu:
  Installed: 0.3.96-0ubuntu2
  Candidate: 0.3.96-0ubuntu2
  Version table:
 *** 0.3.96-0ubuntu2 0
        500 http://archive.ubuntu.com/ubuntu/ precise/main amd64 Packages
        100 /var/lib/dpkg/status

[Allison Karlitskaya (desrt)]

I finally managed to reproduce this on my i386 VM. killall hud-service results in the race just happening between nautilus and unity-panel-service (with contributions from dbus and X). I think that tells us two things:

 1) hud-service was an innocent bystander
 2) the trouble is related to the menus because otherwise why would hud-service be interested?

[Allison Karlitskaya (desrt)]

So the involvement of menus is secondary to the main problem -- nautilus gets itself stuck in a silly loop reading and re-reading the free space on the drive. If a bookmarked directory is also involved then this results in the bookmarks menu also being updated, thus causing the issue we see here.

[Sam_ (and-sam)]

Ryan, thanks a lot for the investigation and upstream report.

[Launchpad Janitor (janitor)]

This bug was fixed in the package nautilus - 1:3.4.0-0ubuntu2

---------------
nautilus (1:3.4.0-0ubuntu2) precise; urgency=low

  * debian/patches/git_copy_off_by_one.patch:
    - "Off-by-one error in count of copied files" (lp: #930944)
  * debian/patches/git_no_freespace_cpu_look.patch:
    - correct free space calculation and avoid cpu loops (lp: #965493)
 -- Sebastien Bacher <email address hidden> Thu, 05 Apr 2012 17:26:23 +0200

[Allison Karlitskaya (desrt)]

Fix is committed upstream now too.