Fedora is going to BTRFS. I guess that means it is being at least considered for RHEL 9 or 10. I can't see RH choosing ZFS unless the license is sorted out.
Red Hat previously added btrfs to RHEL as a "Technology Preview", only to later remove it (they didn't really have anyone left devoting resources to it, IIRC), deciding to focus on stratis / VDO instead [0]. They do have several XFS folks, though (or did, last I knew).
FWIW, SUSE is the Enterprise Linux vendor that has went "all in" on btrfs.
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Two semi-related, personal thoughts:
1. btrfs today feels a lot like reiserfs did (going on / nearly) 20 years ago.
2. I expect Oracle to -- at some point -- integrate ZFS into Oracle (Enterprise) Linux. That seems like a great way for them to win over some "converts" from RHEL.
@AlgorithmicTime you've been shadow banned it seems but you did raise a point that is worth expanding on:
> Oracle owns ZFS. Or, rather, it bought Sun, which was the company which originally wrote ZFS. So, it doesn't really need to worry about the licensing issues.
Oracle owning ZFS doesn't magically absolve them of risk however it does reduce the risk. But with ZFS being open source, another contributor might have a claim if Oracle were to breach the CDDL license with code written by said contributor (similar to the SCO vs UNIX lawsuits of yesteryear).
To get around this Oracle would need to contact all 3rd party contributors and get the to agree to a license change. This would, in all practicality, then be reflected in a new release (like the GP suggested).
However it is now even more complicated than that because OpenZFS (which is what Linux runs) has diverged from ZFS (which Oracle maintain). So while Oracle would need to agree to any changes in the licensing of OpenZFS (as there's still Oracle code present in OpenZFS), Oracle are not the ones maintaining it and nor could they ship their own version of ZFS as Linux kernel modules to answer any concerns with either OpenZFS licensing nor compatibility with other Linuxes running OpenZFS.
Oracle maintains it's own version of ZFS, which has been separate from OpenZFS since Oracle bought Sun. There us no "Oracle code" in OpenZFS, though some of the patents on techniques are owned by Oracle.
If Oracle wanted to ship ZFS on Linux, they would presumably port over their own version and never involve the OpenZFS team. However, Oracle created btrfs, and seem content to stick with it.
> Oracle maintains it's own version of ZFS, which has been separate from OpenZFS since Oracle bought Sun. There us no "Oracle code" in OpenZFS, though some of the patents on techniques are owned by Oracle.
OpenZFS is a fork of ZFS rather than a reimplementation so I'd be very surprised if there wasn't any Oracle code in it (unless you're making a distinction between Sun and Oracle but legally speaking that would all still be owned by Oracle, hence why I didn't make that same distinction myself).
> If Oracle wanted to ship ZFS on Linux, they would presumably port over their own version and never involve the OpenZFS team.
Porting in this case isn't a simple task as there's a lot of "Solarisims" in ZFS that had to be worked around with the Linux port (ZoL -- ZFS on Linux -- didn't happen over night). Plus, and as I'd said earlier, ZFS and OpenZFS have diverged in terms of supported features so a ZFS volume wouldn't be compatible with an OpenZFS volume. I guess this wouldn't bother Oracle since, like most orgs of that size, they have no qualms with creating vendor lock ins. But it certainly wouldn't do much to sell Oracle Linux to the wider ZoL community.
>but legally speaking that would all still be owned by Oracle, hence why I didn't make that same distinction myself)..
The reason the distinction is important is that Sun released that code under the CDDL. If Oracle wanted to somehow claim it couldn't be used, it would require a massive lawsuit that would basically be against the concept of free software.
One assumes that if Oracle decided to do its ZFS on Linux, it would do so under an actual compatible license. Since Oracle owns Oracle's ZFS, they can just release it under GPLv2 (or MIT, BSD, whatever) and not be even potentially doing anything that would let someone sue them.
There is no "just" in "just release it under [another license]". I'd written a detailed rebuttal of why it's not that simple in the GP post to yours: https://news.ycombinator.com/item?id=24331156
Oracle owns ZFS. Or, rather, it bought Sun, which was the company which originally wrote ZFS. So, it doesn't really need to worry about the licensing issues.
I have no relation to either Fedora or RH, but have gone through quite a bit of their mailing lists in the past few months. Fedora adopting btrfs has nothing to do with RHEL and they don't seem to be considering it at all. Red Hat threw all their weight behind XFS with advanced features being added mostly through separate layers (e.g. stratis).
I also have no relationship to RH other than as a user of their free stuff.
Yes when it became apparent that BTRFS was not ready RH did that. It was a slight surprise when it happened if I remember correctly.
I said RHEL v9 OR 10. I guess 9 is unlikely but 10 is a number of years off. If BTFS is a sucess on Fedora and stable then they will surely consider it. That is the point of Fedora...
I work for Red Hat but have no insight into any of the Stratis/Btrfs/etc stuff. I'm just a long time Fedora user.
I would agree with you. Fedora adopting stuff does not mean RHEL will include it, but if it's successful/popular on Fedora then Red Hat will surely be paying attention. RHEL tries to follow Fedora as closely as possible, I would imagine this is a shot for btrfs, but certainly no guarantee.
Redhat has a problem that Fedora doesn't have: they stick to a kernel version through the entire release life cycle. In other words, they are stuck with a specific kernel for at least 10 years.
Btrfs goes though a rapid development; so Redhat has to backport everything to their ancient 3.10 (RHEL7) kernel all the time. That's a lot of work.
Fedora, on the other hand, uses current kernels. They do not have to do this work.
Redhat also cannot choose ZFS while in the license limbo; that's why they push for Stratis.
FWIW, SUSE is the Enterprise Linux vendor that has went "all in" on btrfs.
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Two semi-related, personal thoughts:
1. btrfs today feels a lot like reiserfs did (going on / nearly) 20 years ago.
2. I expect Oracle to -- at some point -- integrate ZFS into Oracle (Enterprise) Linux. That seems like a great way for them to win over some "converts" from RHEL.
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[0]: https://news.ycombinator.com/item?id=14907771