> I _really_ wanted Linux to get a native, modern COW filesystem
Btrfs not good?
(Honest question.)
Btrfs not good?
(Honest question.)
I've had a few issues, but no data loss:
* Early versions of btrfs had an issue where you'd run out of metadata space (if I recall). You had to rebalance and sometimes add some temporary space do that.
* One of my filesystems wasn't optimally aligned because btrfs didn't do that automatically (or something like that -- this was a long time ago.) A very very minor issue.
* Corruption (but no data loss, so I'm not sure it's corruption per se...) during a device replacement.
This last one caused no data loss, but a lot of error messages. I started a logical device removal, removed the device physically, rebooted, and then accidentally readded the physical device while it was still removing it logically. It was not happy. I physically removed the device again, finished the logical remove, and did a scrub and the fsck equivalent. No errors.
I think that's a testament to its resiliency, but also a testament how you can shoot yourself in the foot.
I've never used RAID5/6 on btrfs and don't plan to -- partly because of the scary words around it, but I also assume the rebuild time is longer.
Seemingly regardless of the drives, interface, or kernel, other filesystems paired with LVM or mdraid fail/recover/lie more gracefully. NVMe or SATA (spindles). Demonstrated back-to-back with replacements from different batches.
Truly disheartening, I want BTRFS. I would like to dedicate some time to this, but, well, time remains of the essence. I'm hoping it's something boring like my luck with boards/storage controllers, /shrug.
It's reproducible, the scope needs to be reduced. With work. A lot of testing and variable change/reduction. More than I care for.
The problem: R&R, work/money, etc, all compete for a limited amount of time. I'll spend it how I like, Square? Comments win over rigorous testing with my schedule, thanks.
Why don't you try to reproduce it? Better things to do, this isn't the mailing list? Exactly. Pick a reason, there's plenty.
It feels more user friendly than ZFS, but ZFS is much more feature complete. I used to use btrfs for all my personal stuff, but honestly ext4 is just easier.