[I'm not subscribed to the mailing list, thus please keep me in CC.] I was looking at NILFS2 as a potential solution for a file-system for long-term archival (as in backups or append-only store). In this use-case I would use large CMR or SMR rotational disks (say 4+ TB, WD or Seagate) without any RAID or disk-encryption, connected via USB (thus sudden disconnects are to be expected), used with `restic`, or `rdiff-backup` and `rsync`-like if `restic` doesn't work. As such, the IO pattern during backup would be mostly creating new files, a couple MiB each in case of `restic`, and random reads during `restic` checks. In both cases there is quite some concurrency (proportional to the number of cores). So I was wondering the following: * is NILFS2 suitable for such a use-case? (my assumption is yes, at least based on the features and promises;) * how reliable is the current version (as upstreamed in the kernel) of NILFS2? data-loss of previously written (and `fsync`-ed) files is of paramount importance (especially for files that have been written say days ago); * are there instances of NILFS2 used in production (for any use-case)? I've tried searching on the internet and the email archives, but I couldn't find anything "current" enough. Moreover at least OpenSUSE (and SUSE) have dropped the NILFS2 kernel module from the standard packages (granted JFS was also dropped). Also I'm concerned due to the fact that there isn't any `fsck` for NILFS2 yet. Related to this, could the community recommend an alternative file-system that would fit the bill? (Ext4 and JFS are the only file-systems I have heavily used and relied upon.) Thanks, Ciprian.
