BLAKE3 vs BLAKE2 for btrfs

Published: July 26th 2026 (week 30 of 2026) in linux

A comparison (from 2020) of BLAKE2 and BLAKE3 as btrfs' checksum algorithms. I use blake2b for all my btrfs filesystems.

How to check what checksum algorithm a particular btrfs filesystem uses? The following command will give you plenty of information about the filesystem:

btrfs inspect-internal dump-super /dev/foo

To extract just the checksum type you can use this pipeline:

btrfs inspect-internal dump-super /dev/foo |

awk '/csum_type/ { print $3 }' |

tr -d '()'

blake2b

As typical for btrfs-related questions, I found the inspect-internal command in a post on the Forza's Ramblings blog.