The out-of-tree Bcachefs file-system is ready with its reconcile feature, which previously was known as "rebalance_v2", and what lead developer Kent Overstreet calls the biggest feature to this copy-on-write file-system in the last two years.

Overstreet announced today that the Bcachefs reconcile feature is ready:

"Biggest new feature in the past ~2 years, I believe. The user facing stuff may be short and sweet - but so much going on under the hood to make all this smooth and polished."

This though is an incompatible upgrade for enabling the reconcile functionality. This feature since last month was [1]available in their snapshot/nightly testing channel and has since further stabilized. Overstreet describes it as:

"Reconcile now handles all IO path options; previously only the background target and background compression options were handled.

Reconcile can now process metadata (moving it to the correct target, rereplicating degraded metadata); previously rebalance was only able to handle user data.

Reconcile now automatically reacts to option changes and device setting changes, and immediately rereplicates degraded data or metadata

This obsoletes the commands `data rereplicate`, `data job drop_extra_replicas`, and others; the new commands are `reconcile status` and `reconcile wait`.

The recovery pass `check_reconcile_work` now checks that data matches the specified IO path options, and flags an error if it does not (if it wasn't due to an option change that hasn't yet been propagated)."

Those wanting to learn more about the Bcachefs reconcile functionality can do so via the [2]Bcachefs mailing list .



[1] https://www.phoronix.com/news/Bcachefs-Rebalance-V2

[2] https://lore.kernel.org/linux-bcachefs/slvis5ybvo7ch3vxh5yb6turapyq7hai2tddwjriicfxqivnpn@xdpb25wey5xd/T/#u