> Am 19.01.2018 um 20:00 schrieb Jim Wiggs <[email protected]>: > > As I mentioned in a previous reply, I was not aware that ZIL is now > recoverable. My experience with ZFS for KVM workloads has been solely on > Linux, using ZVOLs for my disk images. The word there was always *mirror > your ZIL* or you risked losing the last ~5 seconds worth of writes if your > ZIL device died.
The concern I’ve read about is that you may be running smoothly with an SSD slog, have a power failure, and find, when you reboot, that the SSD was actually dead, it just hadn’t stopped moving yet – so it never comes back on line. I have no idea whether that is a common failure mode. Back when I was building a couple of larger SmartOS servers, I picked up some ZeusRAM slog devices (supercap-backed DRAM-based dual-ported SAS drives), which seemed to be everybody’s top recommendation. They’re rather pricey, and nobody was suggesting it might be reasonable to mirror them. Maybe they’re just very reliable, but my understanding was always that Illumos would recover transparently from a slog device failure. Best, Chris ------------------------------------------- smartos-discuss Archives: https://www.listbox.com/member/archive/184463/=now RSS Feed: https://www.listbox.com/member/archive/rss/184463/25769125-55cfbc00 Modify Your Subscription: https://www.listbox.com/member/?member_id=25769125&id_secret=25769125-7688e9fb Powered by Listbox: http://www.listbox.com
