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Use FreeBSD or illumos. Increasingly Linux is a fine option too. OpenZFS is the mantle. It's the umbrella for ZFS projects across operating systems: http://ope

by dmpk2k 12y ago

Use FreeBSD or illumos. Increasingly Linux is a fine option too. OpenZFS is the mantle. It's the umbrella for ZFS projects across operating systems: http://open-zfs.org/wiki/Contributors http://open-zfs.org/wiki/Contributors Dead it is not: http://open-zfs.org/wiki/Features http://open-zfs.org/wiki/Features Indeed, there is some fragmentation, but that's being cleaned up thanks to the OpenZFS initiative. Why does OpenZFS need a "tier one" development platform? Historically illumos lead the way, but I rather think a cross-platform filesystem is more useful than one limited to a single OS. In any case, none of this changes that ZFS has been in widespread production use for nearly a decade. HAMMER? Right.

rodgerd 12y ago
If you're going to argue we can trust ZFS because it's been in production use for a decade, it's shittily disingenious to try and paper over the fact that OpenZFS is a fork that diverged from upstream 4 years ago - almost half that timespan. And where is the development effort from that "10 years" going?
- bcantrill 12y ago
  We run ZFS -- specifically, OpenZFS -- in production across all of our datacenters, as do our private cloud customers in theirs. We use it for everything including (notably) our Manta storage service.[1] There is nothing disingenuous in claiming that ZFS (OpenZFS!) has been in production use for a decade! [1] http://open-zfs.org/w/images/0/03/Manta-Dave_Pacheco.pdf http://open-zfs.org/w/images/0/03/Manta-Dave_Pacheco.pdf
  - PhantomGremlin 12y ago
    That link doesn't inspire confidence, for two different reasons: 1) open-zfs.org points to 4 separate operating systems that support ZFS. To wit: illumos, FreeBSD, ZFS on Linux, OpenZFS on OS X. So what about all the other distributions out there, e.g. OpenIndiana? Like I said: Fragmentation. What are the odds that any two of the plethora of distributions are using the same ZFS bits? Which bugs are fixed in which distribution? Which post-Sun features are enabled in which distribution? 2) The PDF mentions ZFS panics and disk corruption, "a dark time" about a year ago. Fortuitously "Matt Ahrens and George Wilson diagnosed the problem". Great! One of the inventors of ZFS and one of the ZFS tech leads from Sun were available. But what about if the average user has a problem? Maybe you can give us Matt's phone number? Is he available for pro bono consulting when Joe Sixpack has a problem? I'd love to believe in ZFS. But it seems to me that, right now, it's only usable when supported by a big player. It's probably great if I go to Joyent and sign up for the Manta Storage Service. But if I have a problem while using ZFS in FreeBSD or in Linux, my only recourse would be to start whining on mailing lists.
    - the_why_of_y 12y ago
      > Great! One of the inventors of ZFS and one of the ZFS tech leads from Sun were available. But what about if the average user has a problem? Maybe you can give us Matt's phone number? Is he available for pro bono consulting when Joe Sixpack has a problem? This works in exactly the same way as for any other file system: if you've got a serious issue with ext4 or XFS you will be happy if you have a RHEL or SLES subscription giving you competent support, and not so happy if you don't.
    - bcantrill 12y ago
      First, you're conflating "cross-platform" with "fragmentation". Yes, ZFS is on illumos, FreeBSD, ZoL, etc. -- but thanks to both the common code base and the well-defined feature flags[1], there is no fragmentation. (You can even take zpools from one system, export them on one OS and import them on another -- something essentially unique to ZFS.) Second, with respect to our Manta experience, the point was not that we hit the issue but that working with the community, we resolved it. Manta hits ZFS way, way, way harder than you ever will (and in particular, hits rollback harder than anyone else ever has), and in that dimension, our experience should inspire confidence. But if you're still concerned, you have two choices: you can either buy ZFS support by buying a product that supports it (thereby making it the problem of one of the "big players" that you cite), or you can appeal to the mailing lists when you have a problem. In that regard, ZFS is no different than any other piece of open source software -- it just happens to be a pretty solid piece of open source software. [1] http://blog.delphix.com/csiden/files/2012/01/ZFS_Feature_Flags.pdf http://blog.delphix.com/csiden/files/2012/01/ZFS_Feature_Fla...
    - dap 12y ago
      > Great! One of the inventors of ZFS and one of the ZFS tech leads from Sun were available. But what about if the average user has a problem? Maybe you can give us Matt's phone number? Is he available for pro bono consulting when Joe Sixpack has a problem? That was my talk. Your summary is a gross mischaracterization on many levels. I'd suggest watching the video. To elaborate a bit: we have almost certainly pushed the code path in question enormously harder than anyone else. Our workload is not even close to representative of even heavy users' experiences. We saw the bug a handful of times in about sixteen million executions. The point isn't that ZFS is buggy, since all complex systems have latent bugs. The point is that if this had been a similar bug with almost any other filesystem, the result would have been unmitigated, undetected user data corruption. Instead, it was detected, characterized, and repaired before user data was ever affected. There was admittedly much more human intervention than we would have liked, but we never returned an incorrect byte to a user. That's a big deal, and that was my point. In terms of support: your choice with any software is to support it yourself or hire others to support it. ZFS is no different in this regard. I apologize if my slide gave the wrong impression, but I can't help but feel you twisted what was clearly incomplete information into a narrative of FUD. If you want the facts, and the talk doesn't answer your questions, do reach out.

by dmpk2k 12y ago

rodgerd 12y ago

If you're going to argue we can trust ZFS because it's been in production use for a decade, it's shittily disingenious to try and paper over the fact that OpenZFS is a fork that diverged from upstream 4 years ago - almost half that timespan. And where is the development effort from that "10 years" going?

bcantrill 12y ago
We run ZFS -- specifically, OpenZFS -- in production across all of our datacenters, as do our private cloud customers in theirs. We use it for everything including (notably) our Manta storage service.[1] There is nothing disingenuous in claiming that ZFS (OpenZFS!) has been in production use for a decade! [1] http://open-zfs.org/w/images/0/03/Manta-Dave_Pacheco.pdf http://open-zfs.org/w/images/0/03/Manta-Dave_Pacheco.pdf
- PhantomGremlin 12y ago
  That link doesn't inspire confidence, for two different reasons: 1) open-zfs.org points to 4 separate operating systems that support ZFS. To wit: illumos, FreeBSD, ZFS on Linux, OpenZFS on OS X. So what about all the other distributions out there, e.g. OpenIndiana? Like I said: Fragmentation. What are the odds that any two of the plethora of distributions are using the same ZFS bits? Which bugs are fixed in which distribution? Which post-Sun features are enabled in which distribution? 2) The PDF mentions ZFS panics and disk corruption, "a dark time" about a year ago. Fortuitously "Matt Ahrens and George Wilson diagnosed the problem". Great! One of the inventors of ZFS and one of the ZFS tech leads from Sun were available. But what about if the average user has a problem? Maybe you can give us Matt's phone number? Is he available for pro bono consulting when Joe Sixpack has a problem? I'd love to believe in ZFS. But it seems to me that, right now, it's only usable when supported by a big player. It's probably great if I go to Joyent and sign up for the Manta Storage Service. But if I have a problem while using ZFS in FreeBSD or in Linux, my only recourse would be to start whining on mailing lists.
  - the_why_of_y 12y ago
    > Great! One of the inventors of ZFS and one of the ZFS tech leads from Sun were available. But what about if the average user has a problem? Maybe you can give us Matt's phone number? Is he available for pro bono consulting when Joe Sixpack has a problem? This works in exactly the same way as for any other file system: if you've got a serious issue with ext4 or XFS you will be happy if you have a RHEL or SLES subscription giving you competent support, and not so happy if you don't.
  - bcantrill 12y ago
    First, you're conflating "cross-platform" with "fragmentation". Yes, ZFS is on illumos, FreeBSD, ZoL, etc. -- but thanks to both the common code base and the well-defined feature flags[1], there is no fragmentation. (You can even take zpools from one system, export them on one OS and import them on another -- something essentially unique to ZFS.) Second, with respect to our Manta experience, the point was not that we hit the issue but that working with the community, we resolved it. Manta hits ZFS way, way, way harder than you ever will (and in particular, hits rollback harder than anyone else ever has), and in that dimension, our experience should inspire confidence. But if you're still concerned, you have two choices: you can either buy ZFS support by buying a product that supports it (thereby making it the problem of one of the "big players" that you cite), or you can appeal to the mailing lists when you have a problem. In that regard, ZFS is no different than any other piece of open source software -- it just happens to be a pretty solid piece of open source software. [1] http://blog.delphix.com/csiden/files/2012/01/ZFS_Feature_Flags.pdf http://blog.delphix.com/csiden/files/2012/01/ZFS_Feature_Fla...
  - dap 12y ago
    > Great! One of the inventors of ZFS and one of the ZFS tech leads from Sun were available. But what about if the average user has a problem? Maybe you can give us Matt's phone number? Is he available for pro bono consulting when Joe Sixpack has a problem? That was my talk. Your summary is a gross mischaracterization on many levels. I'd suggest watching the video. To elaborate a bit: we have almost certainly pushed the code path in question enormously harder than anyone else. Our workload is not even close to representative of even heavy users' experiences. We saw the bug a handful of times in about sixteen million executions. The point isn't that ZFS is buggy, since all complex systems have latent bugs. The point is that if this had been a similar bug with almost any other filesystem, the result would have been unmitigated, undetected user data corruption. Instead, it was detected, characterized, and repaired before user data was ever affected. There was admittedly much more human intervention than we would have liked, but we never returned an incorrect byte to a user. That's a big deal, and that was my point. In terms of support: your choice with any software is to support it yourself or hire others to support it. ZFS is no different in this regard. I apologize if my slide gave the wrong impression, but I can't help but feel you twisted what was clearly incomplete information into a narrative of FUD. If you want the facts, and the talk doesn't answer your questions, do reach out.