Hello Richard, Richard Laager [2016-04-20 0:47 -0000]: > In parallel with mounting fstab sounds reasonable, since mounting filesystems > from fstab and mounting filesystems from ZFS (which happens by default upon > import) are analogous.
Ah, I see. So do file systems from ZFS have a separate equivalent to /etc/fstab? > But I doubt it would be performant. Running > zpool import examines all devices > [...] > Additionally, if you're responding to device events one-by-one, for pools with > more than one disk, there's a question of whether you should import the pool > when disks are missing I think these two make it sufficiently "device unspecific" to make a simple "call this in an udev rule" impractical. > I think the best behavior > is to import a pool: > once all devices are present || It's really best to completely drop the idea of "all devices". It just doesn't work in a world where you even can (and do) hotplug PCI devices (e. g. to replace a faulty disk in a server). Thinking in these terms also quickly gets you down into a rabbit hole of race conditions and too strong locks. > (once sufficient devices are present && That sounds like the right approach. That's more or less what LVM or mdadm are doing. For some RAID modes in mdadm it's possible that you already assemble a device before all members have been detected (e. g. RAID-1 with 3 redundant disks), but LVM gets along with the third member being added afterwards. > a short timeout has expired with no new disks arriving) That again is a part I strongly recommend to drop, as it's not well-defined. Thanks! -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1571761 Title: zfs-import-cache.service slows boot by 60 seconds To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cloud-init/+bug/1571761/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
