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Comment by __turbobrew__ | Hacker News Reader

How can I know what configurations of btrfs lose my data?

I also have had to deal with thousands of nodes kernel panicing due to a btrfs bug in linux kernel 6.8 (stable ubuntu release).

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I thought the usual recommendation was to use mdadm to build the disk pool and then use btrfs on top of that - but that might be out of date. I haven't used it in a while

This is very much a big compromise where you decide for yourself that storage capacity and maybe throughput are more important than anything else.

The md metadata is not adequately protected. Btrfs checksums can tell you when a file has gone bad but not self-heal. And I'm sure there are going to be caching/perf benefits left on the table not having btrfs manage all the block storage itself.

I thought most distros have basically disabled the footgun modes at this point; that is, using the configuration that would lose data means you'd need to work hard to get there (at which point you should have been able to see all the warnings about data loss).

See the part of my comment where the btrfs kernel driver paniced on Ubuntu 24 stable kernel.

We are using a fairly simple config, but under certain heavy load patterns the kernel would panic: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux...

I hear people say all the time how btrfs is stable now and people are just complaining about issues when btrfs is new, but please explain to me how the bug I linked is OK in a stable version of the most popular linux distro?

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