Nearest mdadm equivalent of kernel RAID autostart code?

[Matthew Bloch <matthew@bytemark.co.uk>]

Hi there,

After a lot of compiling static kernels, I'm building a generic one for our
particular mix of servers, so the md code is now modular.  I didn't realise
that I'd lose the automatic array assembly functionality, though I
appreciate reasons for trying to deprecate it.

Can anyone suggest a better shell equivalent of the array assembly
functionality that I can use with a modular md?  So far I've got:

for DEV in 0 1 2 3 4 5 6 7 ; do
  mdadm -Ac partitions -m $DEV /dev/md$DEV
done

But this seems a bit slow as it tears through every device in /dev on each
call (about 30 seconds per mdadm call).  I don't want to have RAID
configuration files on each server if I can avoid it, as I know that all
the info I need will be in the relevant discs' superblocks.

Any better ideas for doing the job?

-- 
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