Bcachefs, an introduction/exploration - blog.asleson.org

[utterances-bot]

Bcachefs, an introduction/exploration - blog.asleson.org

Introduction & background information NOTE: This content is from an internal talk I gave, thus the reason it may read like a presentation So what is bcachefs? bcachefs is a next-generation copy-on-write (COW) filesystem (FS) that aims to provide features similar to Btrfs and ZFS, written by Kent Overstreet Copy-on-write (COW), with goal of performance being better than other COW filesystems Full checksums on everything Mult-device, replication , RAID, Caching, Compression, Encryption Sub-volumes, snapshots Scalable, 50+ TB tested Why the need for another FS?

http://blog.asleson.org/2024/07/24/bcachefs-an-introduction/exploration/

[RlndVt]

Hi, thanks for this blog post; it's a nice overview of the current state of things.

Some notes and a question however. Firstly, I believe btrfs does not have native encryption; nor do I believe btrfs has native caching, layering bcache+btrfs would probably be your best bet for caching

I was also wondering what you mean with the 'dedupe' column? I believe ZFS has support for online deduping, and ZFS, btrfs, and xfs (through reflink) supports manual deduplication. (I'm not sure about bcachefs but I believe some(/one) of the popular offline dedupe apps also work on bcachefs.)

Thanks again for your post!

[tasleson]

Firstly, I believe btrfs does not have native encryption; nor do I believe btrfs has native caching,

I'll look into this, but you're likely correct. I thought it did, but then again my current setup I'm using dm-crypt with btrfs on top. I'll double check and I'll correct this blog post.

I was also wondering what you mean with the 'dedupe' column?

I was referring to the feature of de-duplication, like the functionality provided by VDO. For a background see DevConf presentation

Thanks!

[RlndVt]

I was also wondering what you mean with the 'dedupe' column?

I was referring to the feature of de-duplication, like the functionality provided by VDO. For a background see DevConf presentation

I haven't watched the presentation, but a quick search I believe that is similar to ZFS's online/in-band deduplication. (ZFS's deduplication is the source of the infamous 1GB of RAM for each TB of storage 'myth'.) How does VDO's deduplication compare to ZFS's dedupe option?

See also BTRFS's documentation on in- and out-of-band deduplication. The mentioned duperemove also supports XFS.

[tasleson]

How does VDO's deduplication compare to ZFS's dedupe option?

No idea, but a great question!

Thanks for link to duperemove

[tasleson]

Updated features table