David W Noon writes:
> On Fri, 01 Jul 2011 22:05:12 +0200, Alex Schuster wrote about
> [gentoo-user] LVM filter question:
>
> [snip]
>
> > filter = [ "r|/dev/nbd.*|", "r|/dev/sdd|", "a/.*/" ]
> >
> > This should reject /dev/sdd from scanning. But it doesn't, pvscan
> > spins it up. Any idea why it is not being ignored?
>
> The regular expression that precedes the one involving /dev/sdd
> provides a clue: it would appear that LVM wraps the r.e. with ^ and $
> so that it completes a string.
>
> So, your r.e. should read:
>
> r|/dev/sdd.*|
>
> which decodes to "reject ^/dev/sdd.*$ ".
>
> This suppresses the scans of /dev/sdd1, /dev/sdd2, etc.
>
> Now, you might not have any partitions on /dev/sdd, but LVM cannot
> readily know that without reading the partition table, which spins up
> the drive. I guess LVM doesn't trust or, at least, depend upon udev
> to supply the partition details.
Good idea, didn't think about this. I tried that, but it did not help.
/dev/sdd indeed has no partitions, the whole drive is a LUKS container.
Looks like this just does not work at all. Too bad. I have two big 1.5 TB
drives, one as system drive, the other as identical backup drive. And then
there are five more smaller drives for stuff I do not need regularly. Any
LVM operation takes a while when all those drives have to spin up first.
Another annoying problem is KDE's / Dolphin's trash. When I delete something
to the trash, all drives (or at least some, I have to investigate this
further) that have mounted partitions spin up, one after another.
Wonko
