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Revision as of 22:12, 9 October 2008 by Jmtaylor (talk | contribs) (Kernel Modesetting)

Fedora 10 Boot-Time

Fedora 10 includes multiple boot-time updates, including changes that allow for faster booting and graphic booting changes.


Plymouth is the graphical boot up system debuting with Fedora 10.

  • Adding rhgb on the command line directs Plymouth to load the appropriate plugin for your hardware.
  • The graphical boot splash screen that comes with Plymouth requires kernel mode setting drivers to work best. There are not kernel modesetting drivers available for all hardware yet. To see the graphical splash before the drivers land, add vga=0x318 to the kernel grub command line. This uses vesafb, which does not necessarily give the native resolution for the flat panel, and may cause flickering or other weird interactions with X. Without kernel modesetting drivers or vga=0x318, Plymouth uses a text-based plugin that is plain but functional.
  • Currently, only Radeon R500 and higher users will get kernel modesetting by default. There is work in progress to provide modesetting for R100 and R200. Additionally, Intel kernel modesetting drivers are in development, but not turned on by default.
  • The kernel modesetting drivers are still in development and buggy. If you end up with nothing but a black screen during boot up, or a screen with nothing but random noise on it, then adding "nomodeset" to the kernel boot prompt in grub disables modesetting.
  • Plymouth hides boot messages. To view boot messages, press the [Esc] key during boot, or view them in /var/log/boot.log after boot up. Alternatively, remove rhgb from the kernel command line and plymouth will display all boot messages. There is also a status icon on the login screen to view boot warnings.

Faster Booting

Fedora 10 has had changes made to how it processes starting up.

  • Parallel to the boot process, readahead is now started.
  • Udev may appear to be slower but in fact readahead reads all disk buffers needed for the boot process in the background and shortens the whole boot process. Creation of the readahead file list will be done monthly and can be triggered manually by touching "/.readahead_collect". /etc/sysconfig/readahead can be edited to turn off readahead-collector and/or readahead.

Kernel Modesetting

Kernel modesetting (KMS) can default to either enabled or disabled in the DRM driver and it can be enabled or disabled at boot-time.

  • Both Plymouth and the DDX drivers will detect whether KMS is present and enabled. If it is present and enabled, Plymouth and DDX drivers will take advantage of them.
  • If KMS is not present or it is present but disabled then Plymouth will automatically fall back to the text splash and the DDX driver will automatically fall back to user-space modesetting.
  • Allows for faster user switching, seamless X server switching and graphical panic messages.