That "ZFS helped me remove code" story going around is ironic in that it's describing replacing a custom-built script that does checksumming of files. One of the benefits of that script was detecting data corruption, and ZFS does replace that, because it provides block-level checksumming.

But there are other benefits to having a regularly updated file-level checksum database ... that ZFS doesn't provide. Doing it in ZFS would be dramatically more efficient than my custom script, which is why I requested it back in 2022:

"lazy" file-level checksums, based on awareness of changed blocks · Issue #13809 · openzfs/zfs

Describe the feature you would like to see added to OpenZFS ZFS is uniquely positioned to efficiently provide "lazy" (just in time / cached) file-level checksumming. This might have some of the following properties and behaviors: The adm...

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