[chasil]

Oracle has essential control of both "nextgen" filesystems that should be used in Linux - as Sun, they developed and licensed ZFS, and they are the chief contributors of BtrFS. Their refusal to release ZFS under a license that is compatible with the GPL is keeping it out of Red Hat's distribution.

This move by Red Hat must be seen as a provocation of Oracle, to force either greater cooperation and compliance in producing a stable BtrFS for RHEL, or the release of ZFS under a compatible license. Red Hat has put an end to BtrFS for now, and Oracle will have to go to greater lengths to use it in their clone. Customers also will not want it if it does not run equally well between RHEL and Oracle Linux.

It is obvious that Oracle will have to assume higher costs and support if they want BtrFS in RHEL. Red Hat is certainly justified in bringing Oracle to heel.

Oracle recently committed preliminary dedup support for XFS, so they must be intimately aware of the technical and legal issues behind Red Hat's move.

https://blogs.oracle.com/linuxkernel/upcoming-xfs-work-in-li...

[cjbprime]

Oracle is not the "chief contributors" of Btrfs. If anyone is, it's Facebook. Chris Mason (the btrfs creator) worked for Oracle. He left in 2012.

> This move by Red Hat must be seen as a provocation of Oracle

I doubt it.

[chasil]

A thousand pardons - I am mistaking "initially designed" for current control.

https://en.wikipedia.org/wiki/Btrfs

"... initially designed at Oracle Corporation for use in Linux."

[crudbug]

Oracle uses RHEL for their Unbreakable Linux [0] distribution. The least thing they can do is open up ZFS for the Linux community.

[0] - https://linux.oracle.com/

[chasil]

Seconded. I am in absolute agreement.

[rbanffy]

> open up ZFS for the Linux community.

More likely they'll support it only on their Linux.

[chasil]

This will particularly impact the "Red Hat Compatible Kernel" (RHCK) that is shipped by Oracle Linux.

https://docs.oracle.com/cd/E37670_01/E57668/html/ol_kern_65r...

Assuming that RHEL v8 strips BtrFS, Oracle's RHCK will have to add support back in, and thus no longer be "compatible." Without that support, some filesystems will fail to mount at boot. In-place upgrades from v7 to v8 will be problematic.

Oracle has worked very hard to maintain "compatibility" with Red Hat, even going so far as to accept MariaDB over MySQL. Their reaction to the latest "poison pill" will be interesting.

[lenzgr]

Why would Oracle have to add Btrfs support back into the RHCK? It's exactly the point of this kernel to be 100% identical to upstream RHEL. If an Oracle Linux user needs Btrfs support, it will still be included in the "Unbreakable Enterprise Kernel" (UEK), which Oracle provides as an alternative.

[chasil]

Any BtrFS filesystems in /etc/fstab won't mount if/when an RHCK boots that lacks the filesystem driver.

An in-place upgrade from v7 to v8 could easily get hosed.

[bonzini]

Does Oracle support Btrfs (as opposed to making it just a tech preview) with the compatible kernel? I don't think so, since it's the same code as RHEL. And if not, hosing in-place upgrades is acceptable. RHEL 7 is supported until 2024.