On Sat, 2012-06-09 at 01:38 +0600, Roman Mamedov wrote: > Hello, > > Before the upgrade (on 3.2.18): > > Metadata, DUP: total=9.38GB, used=5.94GB > > After the FS has been mounted once with 3.4.1: > > Data: total=3.44TB, used=2.67TB > System, DUP: total=8.00MB, used=412.00KB > System: total=4.00MB, used=0.00 > Metadata, DUP: total=84.38GB, used=5.94GB > > Where did my 75 GB of free space just went? Btrfs tries to keep a certain ratio of allocated data space to allocated metadata space at all times, in order to ensure that there is always some free metadata space available. In 3.3 (I believe, but haven't actually checked...) this ratio was increased, since people were still complaining about btrfs reporting out of space errors too soon. On a filesystem containing (a relatively small number of) large files, it probably over-allocates the metadata space, which is what you're seeing. I'm not sure if the ratio is tunable. But better to have a bit of unused metadata space than to get 'out of space' errors once you've filled your disk and you're trying to delete some files! -- Calvin Walton <calvin.walton@xxxxxxxxxx> -- 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
