Re: retiring device.map

[Pavel Roskin <proski@gnu.org>]

On Tue, 2008-05-06 at 17:18 +0200, Robert Millan wrote:

> I completely agree.  How do we go about this?  First of all we need support
> for labels, right?

We have it already in the "search" command.  Of course, there is always
room for improvement.  GRUB doesn't recognize Linux swap labels.  It
cannot set root to, say, partition 3 on a disk where partition 1 has the
given label.

Anyway, the fix belongs to the installer.  The first step would be not
to use device.map is it's not needed.  In other words, if it's not a
cross-device install, don't read device.map and don't try to create it.

The second step is figuring out what to do with cross-device installs.
device.map serves as a persistent cache that can become out of date.
Perhaps it could be replaced with a table in memory that only contains
entries relevant to the install.  device.map was more justified in the
days when floppy drives were common.  But if there are still realistic
cases that take a lot of time (say, 10 seconds or more), we need to
address that issue somehow.

device.map is also used in grub-emu, but grub-emu could use a different
names based on the OS device names.

Finally, update-grub should be modified to look for partitions by
labels.  That will allow grub-emu use the same menu as the real
bootloader, while using different device labels.

-- 
Regards,
Pavel Roskin