Mounting root...

[Pawel Jakub Dawidek]

On Mon, Aug 23, 2004 at 03:01:57PM -0500, Dan Nelson wrote:
+> How about maybe blocking on the initial access to a degraded mirror for
+> 5 (just a guess) seconds to see if the other half shows up?  If it
+> doesn't, assume it's never showing up and use what you have.  When the
+> other disk arrives, sync your changes over to it. [...]

I'm waiting for few seconds for the rest of components now, but mounting
root routine doesn't wait for me.
And I'm not going to create provider without given a chance to the rest
components to show up, because I can end up with mirror started on stale
component, because a fresh one showed up with some delay.

+> If geom_mirror keeps
+> an on-disk bitmap of dirty blocks for fast resyncs, copy your data over
+> the other mirror's dirty blocks.  You'll lose whatever changes were
+> made to that disk, but at least the filesystem will be consistent.

Geom_mirror doesn't keep bitmap with dirty blocks in metadata, this will
probably slowdown things a lot.

Synchronization in geom_mirror is based on 'syncid'. Basically one can
set kern.geom.mirror.timeout to 0 and there will be no need to rebuild
if there will be no write to the mirror...

-- 
Pawel Jakub Dawidek                       http://www.FreeBSD.org
pjd at FreeBSD.org                           http://garage.freebsd.pl
FreeBSD committer                         Am I Evil? Yes, I Am!
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-arch/attachments/20040823/323f1387/attachment.bin