bees VS duperemove

Btrfs defrag 'will break up the reflinks of COW data' and 'may cause considerable increase of space usage depending on the broken up reflinks'. To try to fix this, I would run bees to try and deduplicate the now duplicate reflinks. It may be worth doing this from e.g. a livedisk though as out of space errors can cause things to break (so don't upgrade packages till you fix this).

Figuring out which paths are needed outside gcroots'ed closures is pretty complicated. If you're using flakes, the main issue is duplicates, so store optimization and bees may help. With channels, once you update a channel you might as well gc everything else.

bees

I felt more confident with the code/developer/docs. The author knows his stuff regarding btrfs. Like, look at this, it's amazing: https://github.com/Zygo/bees/blob/master/docs/btrfs-kernel.md

I have some time again and wondering if anyone's got Bees, https://github.com/Zygo/bees, running on their Synology.

Even if NixOS doesn't support sending deduplicating syscalls to the kernel, you could use the Btrfs deduping daemon called bees to slowly save space over time. There might be an equivalent for ZFS, too.

This isn't much different than ext4. 0 length files can happen after a crash. You can avoid this by mounting with flushoncommit for the future. See here for details.

Maybe BEES can help you to dedup any blocks, not file.

Very useful for identifying files that may need to get deduplicate or that can be removed entirely. Unfortunately, I don't think this will also find identical directories.

If deleting files isn't what you want, I'd suggest looking into deduplicating tools.

ZFS has its own de duplicator built in, which is nice. It should just deduplicate files and individual extents of files by itself once you enable it. Probably not a good idea on very write-heavy disks, but it's an option.

Other file systems with extent level deduplication can use https://github.com/markfasheh/duperemove to not only deduplicaye files, but also deduplicate individual extents. This can be very useful for file systems that store a lot of duplicate content, like different WINE prefixes. For filesystems without extent deduplication, duperemove should try hard linking files to make them take up practically no disks space.

ZFS now has reflink support, which doesn't require lots of RAM, but isn't done automatically while writing. You need to run something like https://github.com/markfasheh/duperemove

Then duperemove

Filesystems like Btrfs and XFS have support for deduplication, you can use a program like duperemove to save space.

Maybe you could use a file deduplication instead of a block based? https://github.com/markfasheh/duperemove

If not bees, do you run other programs for deduping? I see jdupes has support for BTRFS, https://github.com/jbruchon/jdupes, and also duperemove, https://github.com/markfasheh/duperemove.

It's a good filesystem, I use it with a special setup that needs a filesystem with snapshots. It's been stable for me, I run a duperemovehttps://github.com/markfasheh/duperemove) occasionally and that's about all the maintenance it needs.

With Btrfs or XFS you can easily deduplicate the data with tools like duperemove, potentially saving a lot of space if you've installed many small games.