Pawel Jakub Dawidek writes:
 > On Mon, Sep 17, 2007 at 03:40:05PM +0200, Roch - PAE wrote:
 > > 
 > > Tuning should not be done in general and Best practices
 > > should be followed.
 > > 
 > > So get very much acquainted with this first :
 > > 
 > >    http://www.solarisinternals.com/wiki/index.php/ZFS_Best_Practices_Guide
 > > 
 > > Then if you must, this could soothe or sting : 
 > > 
 > >    http://www.solarisinternals.com/wiki/index.php/ZFS_Evil_Tuning_Guide
 > > 
 > > So drive carefully.
 > 
 > "If some LUNs exposed to ZFS are not protected by NVRAM, then this
 > tuning can lead to data loss or application level corruption.  However
 > the ZFS pool integrity itself is NOT compromised by this tuning."
 > 
 > Are you sure? Once you turn off flushing cache, how can you tell that
 > your disk didn't reorder writes and uberblock was updated before new
 > blocks were written? Will ZFS go the the previous blocks when the newest
 > uberblock points at corrupted data?
 > 

Good point. I'll fix this. I don't know if we look for
alternate uberblock but even if we did, I guess the 'out of
sync' can occur lower down the tree.


-r


 > -- 
 > Pawel Jakub Dawidek                       http://www.wheel.pl
 > [EMAIL PROTECTED]                           http://www.FreeBSD.org
 > FreeBSD committer                         Am I Evil? Yes, I Am!
 > _______________________________________________
 > zfs-discuss mailing list
 > zfs-discuss@opensolaris.org
 > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss

_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss

Reply via email to