New Features

Common Infrastructure

• Until Ubuntu 11.10, the Unix group for administrators with root privileges through sudo had been admin. Starting with Ubuntu 12.04 LTS, it is now sudo, for compatibility with Debian and sudo itself. However, for backwards compatibility, admin group members are still recognized as administrators.
• Automatic Apport crash reporting has been enabled by default again to catch problems early on. It now checks for duplicates on the client side, which will avoid uploading debug data and creating Launchpad bug reports unnecessarily in many cases now.
• pm-utils now has two new scripts to power down USB and various PCI devices in battery mode. A number of desktop packages were fixed to wake up less often. Both of this reduces power consumption and thus battery lifetime.
• DNS resolution is now done through dnsmasq, which should help split-DNS VPNs and faster DNS resolution.

Linux 3.2.12 Kernel

• 12.04 ships with the 3.2.0-23.36 Ubuntu kernel which is based on the v3.2.12 upstream stable linux kernel. Key changes since the v3.0 linux shipped in 11.10 Ubuntu release include:

  • The amd64 -server and -generic kernel flavors have been merged to help reduce the maintenance burden over the life of this LTS release.
  • Non-smp flavor of PowerPC kernel has been removed.
  • anyone needing AUFS is encouraged to migrate to overlayfs.
  • RC6 is enabled by default for Sandy Bridge systems. RC6 is a technology which allows the GPU to go into a very low power consumption state when the GPU is idle (down to 0W). It results in considerable power savings when this stage is activated. When comparing under idle loads with machine state where RC6 is disabled, improved power usage of around 40-60% has been witnessed.

  • We've backported an improved set of jack detection patches from the upstream v3.3 kernel.

  • A set of kexec fixes for arm from v3.3-rc1 have also been backported.

  • We've also conducted an extensive review of Ubuntu kernel configs and made numerous config changes as a result.

GCC 4.6.2 Toolchain

TODO: slanagasek/doko need a good summary of the key changes made and links to upstream information on toolchain, including details of armhf (linker changes).

• upstram updateds have been applied to gcc 4.6.2.

Python Toolchain

TODO: slangasek/barry need a good overview of the python toolchain, and pointers to migration path.

• upstream updates have been applied to Python 2.7, Python 3.2,

• Python 3 newly ported packages include: python-dbus, python-feedparser, germinate, lazr.ui, wadllib, python-defer, python-keyring, python-qt4

Upstart 1.5

Upstart 1.5 provides ...

TODO: slangasek/james hunt need to know summary of 1.5 release, and how much of the key changes from 1.4 to fold in.

This release also included changes from 1.4:

• New "setuid" and "setgid" stanzas to allow a job to be run as a specified user.

• Default logging of job output:

  • All job output is logged to "/var/log/upstart/<job>.log" by default.

  • Log files are rotated daily by default using logrotate(8). See "/etc/logrotate.d/upstart".

  • Logging can be controlled via the console stanza and by new command-line options "--default-console", "--logdir" and "--no-log".

  • Improved "upstart-udev-bridge" to handle bad hardware that exposes garbage data to userspace.

Known Issues

Boot, Installation and Post-Installation

• omap3/omap4 netboot images are known to generate a too small boot partition. (806751)

Upgrades

• Aptitude does not work on 64 bit systems without disabling multiarch in /etc/dpkg/dpkg.cfg.d/multiarch . (831768)

Kernel

• On ARM omap imagesd the networking support for the Beagle XM board is broken (838200)