On Wednesday, 12 October 2016 4:03:27 PM AEDT Craig Sanders via luv-main wrote: > > The failure modes of SSD are quite different to the failure modes > > of spinning media. I expect it will be some years before there is > > adequate research into how SSDs fail and some more years before > > filesystems develop to work around them. ZFS and WAFL do some > > interesting things to work around known failure modes of spinning > > media, they won't be as reliable on SSD as they might be because of > > the spinning media optimisation. > > I'd still use some kind of raid-1/mirroring anyway, no matter what kind > of drives I had. raid isn't a substitute for backups, but it does reduce > the risk that you'll need to restore from backup (and the downtime and > PITA-factor that goes along with restoring) > > also, there's no way for ZFS to correct any detected errors if there's > no redundancy.
The ZFS copies= feature is designed to operate in single-disk mode. The ZFS metadata has 1 more copy than the data, so even without using copies=2 you will have multiple copies of metadata on a single disk. But whether that does any good on SSD is anyone's guess at the moment. > i don't mind paying double for storage. it's a bit painful at purchase > time, but that's quickly forgotten. and a lot less painful than the time > and hassle required to restore from backup, and losing everything new or > modified since the previous backup (nightly, but that's still up to a > full day's worth of stuff that could be lost. Now that i've got rootfs > on ZFS, I can snapshot frequently and backup more often with zfs send) It's a pity that the options for RAID on laptops are so poor. Thinkpads used to have the option of buying a disk bay to replace the CD/DVD drive but I don't know if that is still available and it was always quite expensive. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/ _______________________________________________ luv-main mailing list [email protected] https://lists.luv.asn.au/cgi-bin/mailman/listinfo/luv-main
