On Wed, Oct 12, 2016 at 03:35:34PM +1100, [email protected] wrote: > On Wednesday, 12 October 2016 2:46:01 PM AEDT Craig Sanders via luv-main > wrote: > > yes, but you can't pipe `btrfs send` to `zfs recv` and expect to get > > anything useful. my backup pool is zfs. > > In the early days the plan was to have btrfs receive not rely on > BTRFS, so you could send a snapshot to a non-BTRFS filesystem. I > don't know if this is a feature they continued with.
nope. from what i've read, they originally intended to make it tar compatible but tar couldn't do what they needed, so they dropped that idea. > Last time I was buying there wasn't much price difference between SATA > and NVMe devices. Usually buying 2 medium size devices is cheaper > than 4 small devices. right, but there's a difference between the price of Crucial SSDs and Samsung or Intel. There's also a price difference between having to buy a pci-e nvme card and not having to buy one. > > PCI-e slots are in very short supply. and my m/b doesn't have any > > nvme sockets. > > That's a problem for you then. well, yes, of course it is. we're talking about my system here, and why I choose 4 cheap SATA SSDs rather than two pci-e SSDs. > > i'd still want to buy them in pairs, for RAID-1/RAID-10 (actually, > > ZFS mirrored pairs) > > 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. 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) craig -- craig sanders <[email protected]> _______________________________________________ luv-main mailing list [email protected] https://lists.luv.asn.au/cgi-bin/mailman/listinfo/luv-main
