Victor Hooi posted on Sat, 11 Oct 2014 22:07:12 +1100 as excerpted: > I have a Ubuntu 14.04 Server host using BTRFS that seems to show large > discrepancies between the output of du (73 GB used) and df (125 GB > used). A sampling from the FAQ: https://btrfs.wiki.kernel.org/index.php/FAQ#Help.21_Btrfs_claims_I.27m_out_of_space.2C_but_it_looks_like_I_should_have_lots_left.21 https://btrfs.wiki.kernel.org/index.php/FAQ#Aaargh.21_My_filesystem_is_full.2C_and_I.27ve_put_almost_nothing_into_it.21 https://btrfs.wiki.kernel.org/index.php/FAQ#Why_is_free_space_so_complicated.3F https://btrfs.wiki.kernel.org/index.php/FAQ#Why_is_there_so_much_space_overhead.3F Basically, use btrfs filesystem show and btrfs filesystem df on btrfs. You may also wish to use the compress mount-option, and if you're using btrfs snapshotting, consider regularly thinning out the old snapshots. Additionally, be aware that snapshot-aware defrag is disabled ATM as it wasn't scaling well, so if you're using snapshots, anything you defrag will take up more room as only the snapshot you point defrag at is defragged, while the other snapshots are still pointing to the old version and won't free that space until the snapshots are removed. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
