Re: (boot time consequences of) Linux mdadm superblock question.

From: martin f krafft
Date: Wed Feb 17 2010 - 18:51:08 EST


also sprach Neil Brown <neilb@xxxxxxx> [2010.02.18.1224 +1300]:
> Using user-space autodetection, you can plug "mdadm -I" into udev,
> and have arrays assembled as they are found, and filesystems
> mounted as arrays are assembled, and then you just have to wait
> for the root filesystem to appear, not for "all devices".

The mdadm experimental package offers this via debconf (default off
for now). I would appreciate testers â I literally whacked this up
on a rainy Sunday with an hangover, and while it seems to work fine,
it's probably got warts.

If you don't run Debian or a derivative, you can get the files from
debian/initramfs/* in git://git.debian.org/pkg-mdadm/mdadm.git or

http://git.debian.org/?p=pkg-mdadm/mdadm.git;a=tree;f=debian/initramfs;hb=HEAD

don't be scared off by the complexity, incremental assembly actually
bypasses most of the (shell) code in both scripts.

> Yes, you could make the in-kernel autodetection smarter so it
> doesn't have to wait quite so long, but that would make it quite
> a bit more complex, and it is harder to maintain the complexity in
> the kernel.

It is definitely a user-space task, if you ask me.

--
martin | http://madduck.net/ | http://two.sentenc.es/

windows 2000: designed for the internet.
the internet: designed for unix.

spamtraps: madduck.bogus@xxxxxxxxxxx

Attachment: digital_signature_gpg.asc
Description: Digital signature (see http://martin-krafft.net/gpg/)