nash, cpio and linuxrc

[Gildas Bayard]

Hello,

First of all, please direct me to an other mailing list if I'm going off
topic.
I've investigated a bit the initrd system and there are some questions I
could no find answers for:
- why are regular desktop distributions always using the initrd system?
I understand that this system is mandatory to load exotic scsi drivers
or add a pause when booting to usb but I wonder why it is always used
- on kernel 2.4 (red hat 9) the initrd image is an ext2 filesystems. It
contains a linuxrc nash script. On kernel 2.6 (fedora 3) the initrd is a
cpio archive and does not contains a linuxrc script. Could someone
briefly explain me why these differences? Particularly I wondering about
3 things:
1) I tried to repack my custom initrd ext2 filesystem into a cpio
archive and found that when packed as a cpio archive it's not executing
my linuxrc script (is it the way it's supposed to be?)
2) What are the differences between pivot_root and switch_root (new in
2.6) ?
3) Why using nash in the first place? Could we just wait until the end
of the linuxrc script? At that time the kernel would move to the new
root fs (whitout the need for pivot_root or switch_root)

And finally, if I'm right the end of the nash script (after switch_root)
is never executed?

Gildas