去wiki的链接 http://wiki.ubuntu.org.cn/Ubuntu_9.10_% ... 8%E8%AE%B0
The minimum memory requirement for Ubuntu 9.10 is 256 MB of memory. Note that some of your system's memory may be unavailable due to being used by the graphics card. If your computer has only the minimum amount of memory, the installation process will take longer than normal, but will complete successfully, and the system will perform adequately once installed.
Systems with less memory may be able to select "Install Ubuntu" from the boot menu to run just the installer, rather than the whole desktop, or may be able to use the alternate install CD.
2.1 Recommended packages installed by default
In accordance with the Debian Policy Manual (which says "The 'Recommends' field should list packages that would be found together with this one in all but unusual installations"), the package management system now installs packages listed in the Recommends: field of other installed packages as well as Depends: by default. If you want to avoid this for specific packages, use apt-get --no-install-recommends; if you want to make this permanent, set APT::Install-Recommends "false"; in /etc/apt/apt.conf. Be aware that this may result in missing features in some programs.
(This change was made in Ubuntu 8.10.)
2.2Hibernation may be unavailable with automatic partitioning
The default partitioning recipe in the installer will in some cases allocate a swap partition that is smaller than the physical memory in the system. This will prevent the use of hibernation (suspend-to-disk) because the system image will not fit in the swap partition. If you intend to use hibernation with your system, you should ensure that the swap partition's size is at least as large as the system's physical RAM. (354126)
2.3 Other OS options not shown in boot menu when installing with Ubuntu 9.10 RC
After installation from the Ubuntu 9.10 Release Candidate, other installed operating systems are not correctly displayed in the boot menu. To correct this, users should run sudo update-grub from the commandline after rebooting to their installed Ubuntu system. (456776)
Users of Ubuntu 9.04 can upgrade to Ubuntu 9.10 by a convenient automated process. Users of older Ubuntu releases need to upgrade to Ubuntu 9.04 first, and then to 9.10. Complete instructions may be found at http://www.ubuntu.com/getubuntu/upgrading
Kubuntu users can upgrade directly from Kubuntu 8.04 to Kubuntu 9.10. Users upgrading in this way are advised to also read the release notes for Ubuntu 8.10 and for Ubuntu 9.04, as the issues described there will in most cases also apply.
3.1Setting wireless regulatory domain via module option no longer supported
Ubuntu 9.10 enables the CRDA wireless regulatory framework for controlling which wireless channels are usable and visible in a particular location. If you previously had to use the module option similar to that below in /etc/modprobe.d/options to allow access to certain channels in your locality then you may find that wireless will not function at all:
* options cfg80211 ieee80211_regdom=EU
You should remove this kernel module option on upgrade to Ubuntu 9.10 and use the iw reg command instead.
(This change was made in Ubuntu 9.04.)
3.2 Upgrade from beta must be triggered manually
A bug in the apt package included in the Ubuntu 9.10 Beta prevents automatic notification of available package updates. Users who have installed or upgraded to Ubuntu 9.10 prior to the Release Candidate should ensure that updates are being made available by running update-manager manually, clicking Check, and installing the presented updates. (449535)
3.3 X server crashes when using a wacom tablet
The wacom driver in Ubuntu 9.10 supports automatic configuration, but it conflicts with manual device entries for wacom tablets in /etc/X11/xorg.conf, causing the X server to crash either on startup or shutdown. Please comment out or remove the entries from xorg.conf to get rid of the crashes. (358643)
3.4 Kubuntu may keep unneeded guidance power package
The kubuntu upgrade may leave the no longer needed packages "kde-guidance-powermanager" or "guidance-power-manager" installed. Those can be removed.
3.5 Ctrl-Alt-Backspace disabled by default in Xorg, configured via XKB
Since Ubuntu 9.04, the Ctrl-Alt-Backspace key combination to force a restart of X is now disabled by default, to eliminate the problem of accidentally triggering the key combination. In addition, the Ctrl-Alt-Backspace option is now configured as an X keymap (XKB) option, replacing the X server "DontZap" option and allowing per-user configuration of this setting.
As a result, enabling or disabling the Ctrl+Alt+Backspace shortcut can now be done easily from the desktop.
3.5.1 Enabling Ctrl-Alt-Backspace for Ubuntu
# Select the "Layouts" tab and click on the "Layout Options" button.
# Select "Key sequence to kill the X server" and enable "Control + Alt + Backspace".
3.5.2 Enabling Ctrl-Alt-Backspace for Kubuntu
* Click on the Application launcher and select "System Settings"
* Click on "Regional & Language".
* Select "Keyboard Layout".
* Click on "Enable keyboard layouts" (in the Layout tab).
* Select the "Advanced" tab. Then select "Key sequence to kill the X server" and enable "Control + Alt + Backspace".
For further information, see: https://wiki.ubuntu.com/X/Config/DontZap
3.6 Change in notifications of available updates
Ubuntu 9.10 launches update-manager directly to handle package updates, instead of displaying a notification icon in the GNOME panel. Users are notified of security updates on a daily basis, but for updates that are not security-related, users will only be prompted once a week.
Users who wish to continue receiving update notifications in the previous manner can restore the earlier behavior using the following command:
gconftool -s --type bool /apps/update-notifier/auto_launch false
(This change was made in Ubuntu 9.04.)
4. Other known issues
4.1 Switching to ext4 requires manually updating grub
If you choose to upgrade your / or /boot filesystem in place from ext2 or ext3 to ext4 (as documented on the ext4 wiki), then you must also use the grub-install command after upgrading to Ubuntu 9.04 to reinstall your boot loader. If you do not do this, then the version of GRUB installed in your boot sector will not be able to read the kernel from the ext4 filesystem and your system will fail to boot.
4.2 Avahi will not start if a .local domain is present
The avahi-daemon package, which implements the mDNS "zeroconf" standard, includes a check to avoid running when a conflicting .local DNS domain is present. It is reported that some ISPs advertise such a .local domain on their networks, which will leave Ubuntu 9.10 hosts unable to see names advertised on the local network (327362).
To force the use of mDNS on a network configured this way, users can run the commands:
sudo sed -i -e'/AVAHI_DAEMON_DETECT_LOCAL/s/1/0/' /etc/default/avahi-daemon
sudo service avahi-daemon start
4.3 Kubuntu GUI package manager does not warn about installing from unsigned package repositories
The kpackagekit package manager used in Kubuntu 9.10 does not notify users if the packages they are installing come from repositories that are not secured with PGP. Users who have unsigned package repositories in their /etc/apt/sources.list configuration and wish to be informed of any packages installed from these sources should use the apt-get commandline tool as a workaround. (256245)
4.4 Amarok will not offer to download additional codecs when running Kubuntu from the live CD
When started from the live session, Amarok will not offer to download additional media codecs when needed, so, for example, it will be unable to play MP3 files. This will work normally after the system is installed to the hard disk. (362538)
4.5 Sparc not supported by Ubuntu 9.10
The upstart init system in Ubuntu 9.10 fails to work on the sparc architecture due to an undiagnosed SIGBUS error. Users of Ubuntu on sparc are advised to remain on Ubuntu 9.04 instead of upgrading to 9.10. Assistance in resolving this architecture-specific bug for Ubuntu 10.04 is welcome. (436758)