MegaBrutal posted on Tue, 02 Dec 2014 06:54:47 +0100 as excerpted: > Hi all, > > I know there is a btrfstune, but it doesn't provide all the > functionality I'm thinking of. > > For ext2/3/4 file systems I can get a bunch of useful data with "tune2fs > -l". How can I retrieve the same type of information about a BTRFS file > system? (E.g., last mount time, last checked time, blocks reserved for > superuser*, etc.) > > * Anyway, does BTRFS even have an option to reserve X% for the > superuser?
btrfs-show-super, btrfs filesystem show, and btrfs filesystem df, show various btrfs-specifics of the filesystem. Last check time doesn't really apply, as the kernel automatically does a lot of checks dynamically at mount and btrfs check isn't designed to be run routinely, only to repair a broken filesystem when mounting with the recovery option, etc, fails. As for reserving a percentage for superuser, btrfs doesn't do that directly. There is the GlobalReserve space (as shown by btrfs fi df) for use by the filesystem itself. Other than that, btrfs quotas could I think be (ab)used to reserve superuser space, but they're definitely optional, and I always recommend not using them if you can avoid it due to the additional complexity/overhead/bugs they add. There's also btrfs property get/set/list, for some of what tune2fs would do plus a lot more btrfs specific stuff and not just on the filesystem but on devices, subvolumes and individual files too, but while the property infrastructure and some basics are there, I think there's more planned that has yet to be implemented. -- 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 majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
