Re: [linux-lvm] devices.filter changed behaviour in 80ac8f37d6

[Peter Rajnoha <prajnoha@redhat.com>]

On 09/07/2015 03:44 PM, Chris Webb wrote:
> (I note from the pvscan(8) man page that global_filter applies to pvscan
> --cache but not standard filter, which sounds like another good reason
> to switch to global_filter!)

Yes, exactly. The idea behind filter and "global_filter" split is that
the global_filter applies globally on system scope (in our context of
lvmetad, it means lvmetad will see everything that "global_filter" allows,
not taking care about the "filter").

Then each LVM client (all LVM commands except pvscan --cache) can use
different "filter" for the information that lvmetad returns.

So you have two levels of filtering here: global one and client-side one
(that's exactly the split between "to update lvmetad" and
"to retrieve info from lvmetad" filter chain I described in my previous
post).

-- 
Peter