> From: Neil Perrin [mailto:neil.per...@oracle.com] > > > you lose information. Not your whole pool. You lose up to > > 30 sec of writes > > The default is now 5 seconds (zfs_txg_timeout).
When did that become default? Should I *ever* say 30 sec anymore? In my world, the oldest machine is 10u6. (Except one machine named "dinosaur" that is sol8) > I believe George responded on that thread that we do handle log mirrors > correctly. > That is, if one side fails to checksum a block we do indeed check the > other side. > I should have been more cautious with my concern. I think I said I > don't know if we handle > it correctly, and George confirmed we do. Sorry for the false alarm. Great. ;-) Thank you. So the recommendation is still to mirror log devices, because the recommendation will naturally be ultra-conservative. ;-) The risk is far smaller now than it was before. So make up your own mind. If you are willing to risk 5sec or 30sec of data in the situation of (a) undetected failed log device *and* (b) ungraceful system crash, then you are willing to run with unmirrored log devices. In no situation does the filesystem become inconsistent or corrupt. In the worst case, you have a filesystem which is consistent with a valid filesystem state, a few seconds before the system crash. (Assuming you have a zpool recent enough to support log device removal.) _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
