2012/1/10 Michal Suba <michal.suba@xxxxxxxxxxx>: > Hello > > we are currently investigating performance issue on system runing above > btrs filesystem. Is it possible, that performance is impacted by lack of > free space? Also, how to get info about real free space on btrfs volume? > > # btrfs-show /dev/sdb1 > Label: opt uuid: 28a55827-e677-47a9-98d5-d31eb3d71436 > Total devices 1 FS bytes used 167.83GB > devid 1 size 240.00GB used *229.25GB* path /dev/sdb1 > > Btrfs Btrfs v0.19 > > # btrfs filesystem df /opt > Data: total=213.23GB, used=165.26GB > System, DUP: total=8.00MB, used=40.00KB > System: total=4.00MB, used=0.00 > Metadata, DUP: total=8.00GB, used=2.57GB > > # df -h /opt > Filesystem Size Used Avail Use% Mounted on > /dev/sdb1 240G 171G 59G 75% /opt > > How come that there is difference detween btrfs-show and df .. 40GB Is the > space really usead or can I claim it back? (there are no snapshots) > > # btrfs subvolume list /opt > # > The btrfs-show command is being deprecated. It's output can be easy to misunderstand, but it probably won't be corrected since it's going away at some point. Basically, what this is telling you is that 229.25GB is "committed" (213.23GB Data + 2 x8.00GB Metadata (because it's duplicated) + 2 x 8.00MB System. However, all the "committed" space is not being used (which is clearer in the 'btrfs filesystem df' command). -- 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
