Re: Mounting root...

From: Pawel Jakub Dawidek (pjd_at_FreeBSD.org)
Date: 08/23/04

  • Next message: Brooks Davis: "Re: Mounting root..." 
    Date: Mon, 23 Aug 2004 22:38:55 +0200
To: Dan Nelson <dnelson@allantgroup.com>

    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@FreeBSD.org                           http://garage.freebsd.pl
FreeBSD committer                         Am I Evil? Yes, I Am!

  • Next message: Brooks Davis: "Re: Mounting root..."