On Thu, May 24, 2018 at 05:51:11PM +1000, Paul van den Bergen wrote:
Is zfs in kernel space yet? or still user land only?
Kernel. I don't think anyone has used the ZFS FUSE module for anything real for years - zfsonlinux (ZoL) has been around since 2008. I've been using it since 2010. http://zfsonlinux.org/ The one minor hassle is that it isn't, and probably never will be(*) in the mainline linux kernel. That means you have to compile and install the kernel module. This is terribly, terribly difficult: apt-get install zfs-dkms Actually, the full set of packages you'd want to install on debian or ubuntu is: apt-get install zfs-initramfs zfs-zed zfsnap zfsutils-linux spl spl-dkms zfs-dkms * spl & spl-dkms are the Solaris Porting Layer to enable zfs-dkms to compile and link and work with the linux kernel.. * zfsutils-linux contains the zpool, zfs, etc commands. * zfs-initramfs adds support for zfs to the initramfs to enable pools to be imported in the initrd. also enables rootgs on zfs. alternatively, use * zfs-dracut instead of zfs-initramfs if you use dracut. * zfs-zed monitors zfs/zpool events and emails you an alert if there's any problem. * zfsnap is a nice, very flexible snapshot scheduling program (e.g. automated creation and deletion of hourly, daily, weekly, monthly etc snapshots). Works well with the simplesnap package for backing up snapshots to another pool (on the same machine, or over the network to another machine running zfs). BTW, I would strongly advise using 'apt-mark hold' to put the zfs packages AND your linux-image-* and linux-headers-* on hold. spl & zfs often need to be tweaked for new kernel releases, and it's fairly common for there to be a few days or even weeks between the time a new kernel version is packaged for debian and the spl-dkms & zfs-dkms packages are updated to match. Also, I don't think it's a good idea to just upgrade the zfs modules along with any regular 'apt-get upgrades'...IMO, something critically important like a filesystem upgrade should only be done when you need/want to upgrade it. Unhold them when you're ready to upgrade, perform the upgrade, then hold the packages again. I do the same thing with the proprietary nvidia driver nvidia-kernel-dkms. Odd things can happen to X when X is running on one version of nvidia.ko, but the underlying module has been upgraded. By "odd" I mean that X will still continue running but some programs (e.g. the linux steam client) will refuse to start until you reboot with the new driver. Mostly I just don't want to have to close down all my browser windows and terminals and tmux sessions etc and reboot until I'm ready to do so. There are a few other packages I also hold so that they only upgrade when I want them to. Postgresql, for example. and Firefox and Chromium. (*) Unless Oracle re-licenses(**) it as BSD or something else that's GPL compatible - which seems very unlikely. (**) ZFS' license is Sun's CDDL. This is a free license by any definition, including the FSF's. It just happens to be incompatible with the GPL, so you can't distribute binaries containing both GPL & CDDL code. There's No problem with compiling or using such combined binaries yourself, though. And there's no problem with distributing helper scripts that automate the process of compiling or linking such binaries (like the zfs-dkms package).
I'd definitely use zfs in BSD or solaris without hesitation over LVM.
There's no reason not to do so in Linux, either.
Not sure about Mac - not familiar with the native FS for that space at all - though I have no doubt one could install zfs without too much hassle.
Dunno either. I heard that Apple were going to switch to ZFS or at least offer it as an option but then decided not to. That was quite a few years ago now and is only a vague half-memory. I think there's at least one open source project bringing openzfs to the mac, similar to how zfsonlinux brings openzfs to linux....but I don't really care about macs so don't pay much attention to apple or mac news. craig -- craig sanders <cas@taz.net.au>