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The Btrfs file system has been in Technology Preview state since the initial release of Red Hat Enterprise Linux 6. Red Hat will not be moving Btrfs to a fully supported feature and it will be removed in a future major release of Red Hat Enterprise Linux.

The Btrfs file system did receive numerous updates from the upstream in Red Hat Enterprise Linux 7.4 and will remain available in the Red Hat Enterprise Linux 7 series. However, this is the last planned update to this feature.

Red Hat will continue to invest in future technologies to address the use cases of our customers, specifically those related to snapshots, compression, NVRAM, and ease of use. We encourage feedback through your Red Hat representative on features and requirements you have for file systems and storage technology.


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    Honestly I wish JFS got more love. It’s a simple, solid filesystem that just works and solves most practical problems (e.g. there’s no initialization-time limit on inodes) without requiring you to learn how to administer your filesystem separately.

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      RedHat pushes XFS for that kind of use case. My impression of JFS was that it was similar to XFS but less widely used. What are JFS’s advantages? Can it do online resize?

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        Well, XFS can do online resize too, so it won’t be JFS’s advantage.

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          JFS can be resized online, at least according to the documentation (I’ve never done it) when used in conjunction with LVM.

          The advantage of JFS, to me, is simplicity. It “just works” because there aren’t a lot of features. It doesn’t do online storage pooling or have its own RAID implementation, but I don’t need those for my little laptop. Btrfs and ZFS have so many features that I will never use.

          I guess JFS just appeals to the minimalist in me. Note that I’m not dogmatic about it: I use other filesystem where they fill a need. But for “I just need a zero-maintenance, fire-and-forget filesystem with decent performance for desktop workloads,” I use JFS.

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        Meanwhile I still have systems I need to move off JFS, but they’ve been so stable and working so well I’m almost afraid to move to newer and less mature technologies.

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          Interesting and SLES still uses it by default. What’s going on here ?

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            There is a reasonable explanation from a former Red Hat developer who worked on btrfs. I have quoted most of his comment for convenience:

            People are making a bigger deal of this than it is. Since I left Red Hat in 2012 there hasn’t been another engineer to pick up the work, and it is a lot of work.

            For RHEL you are stuck on one kernel for an entire release. Every fix has to be backported from upstream, and the further from upstream you get the harder it is to do that work.

            Btrfs has to be rebased every release. If moves too fast and there is so much work being done that you can’t just cherry pick individual fixes. This makes it a huge pain in the ass.

            Then you have RHEL’s “if we ship it we support it” mantra. Every release you have something that is more Frankenstein-y than it was before, and you run more of a risk of shit going horribly wrong. That’s a huge liability for an engineering team that has 0 upstream btrfs contributors.

            The entire local file system group are xfs developers. Nobody has done serious btrfs work at Red Hat since I left (with a slight exception with Zach Brown for a little while.)


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              Pure speculation on my part: RHEL/CentOS uses XFS now by default. I guess this is “good enough” and due to changing requirements of their customers, mostly towards virtualization, container technology, overlay filesystems etc., btrfs became a solution looking for a problem?

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                When talking about RedHats customers: many of them use RAID setups… So I asked today at my clients site, and got shown the following page:


                RAID0: OK

                RAID1: Mostly okay (may get stuck irreversibly)

                RAID10: Mostly okay (may get stuck irreversibly)

                RAID56: Unstable. Write hole still exists, parity not checksummed

                So, this is the reason why btrfs was not even considered as a trial there. They had definitely looked into it.

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                Maybe they have a plan to use ZFS at some point? I wish they had included some explanation for dropping support.

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                  My suspicion is that when Red Hat added btrfs to RHEL 6 as a technology preview they expected it to stabilize and to move to a fully supported thing within a major release or two of RHEL, but now Red Hat’s engineering no longer believes that this is going to happen soon enough. Based on a three to four year release cycle, RHEL 8 is probably going to be released within a year (RHEL 7 came out June 2014), so now is about when Red Hat could be making engineering decisions about what will be included and what won’t be.