[OpenAFS] Re: 1.6 and post-1.6 OpenAFS branch management and schedule

Andrew Deason adeason@sinenomine.net
Thu, 17 Jun 2010 16:12:48 -0500


On Thu, 17 Jun 2010 15:54:25 -0500
Andrew Deason <adeason@sinenomine.net> wrote:

> And as has been mentioned elsewhere in the thread, you need to wait for
> the VG hierarchy summary scan to complete, no matter how fast salvaging
> is or how many you do in parallel. That involves reading the headers of
> all volumes on the partition, so it's not fast (but it is very fast if
> you're comparing it to the recovery time of a 1.4 unclean shutdown)

Also, while I keep talking about this, what I haven't mentioned is that
it may be solvable. Although I've never seen any code or even a
complete plan for it yet, recording the VG hierarchy information on disk
would obviate the need for this scan. Doing this would allow you to
salvage essentially instantly in most cases, so you might be able to
recover from an unclean shutdown and salvage 100s of volumes in a few
seconds.

Again, not in 1.6, but it may happen soon enough as something to
transition to away from fast-restart.

-- 
Andrew Deason
adeason@sinenomine.net