Fails to connect and synchronize after bad system shutdown

[Ricardo Graça]

After an incorrect system shutdown (power failure, pressing the power button for more than 4 seconds instead of soft shutdown, etc) Ubuntu One control panel fails completely with the message "DBusException: org.freedesktop.DBus.Error.NoReply: Did not receive a reply". After analyzing the log files at ~/.cache/ubuntuone/log/ the problem seems to be a corrupt file (0-byte size) in ~/.local/share/ubuntuone/syncdaemon/tritcask. Removing this corrupted file restores full functionality. Note that this problem causes ubuntuone-syncdaemon to continually start and kill itself to infinity with big toll on cpu usage making the system very unresponsive. Of course synchronization fails when this situation occurs.
There is only one way to reproduce this that I'm aware of and it's not pretty...

Steps to reproduce:
1. Open Ubuntu One control panel and start syncing some files
2. Turn off your computer by force without a clean shutdown process
3. Turn on the pc and go to the Ubuntu One control panel

Expected results:
Ubuntu One control panel opens without errors, is able to connect to the server and sync files correctly

Actual results:
Errors on control panel, synchronization fails to start and high cpu usage due to ubuntuone-syncdaemon starting and killing itself over and over again

Note that it's practically impossible to kill the ubuntuone-syncdaemon process because the process number changes several times per second.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: ubuntuone-control-panel 1.0.0-0ubuntu1.1
ProcVersionSignature: Ubuntu 2.6.38-8.42~ppa2-lowlatency 2.6.38.2
Uname: Linux 2.6.38-8-lowlatency i686
Architecture: i386
Date: Fri Jul 22 21:46:18 2011
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release i386 (20110427.1)
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=pt:en
 PATH=(custom, user)
 LANG=pt_PT.UTF-8
 SHELL=/bin/bash
SourcePackage: ubuntuone-control-panel
UpgradeStatus: No upgrade log present (probably fresh install)