On Jan 24, 2013, at 5:44 PM, Adam Williamson <awill...@redhat.com> wrote: > > Just about everything in btrfs is really different :) I'm still wrapping > my head around it too. But as far as possible, the 'legacy' tools should > show something as accurate and useful as they can, I believe.
For mount, the only issue I know of is that it doesn't show subvolume mounted. Ubuntu reportedly does (I don't use it so I can't confirm/deny), even though it's using older btrfs-progs, and older linux-utils. So I'm not sure why Fedora doesn't show subvolumes in mount. I have to do cat /proc/self/mountinfo to get this information on Fedora. For df, it's maybe more challenging. The use cases where it's a problem: small devices, e.g. less than 100GB and also not formatted with the mixed data/metadata option; and pushing the usage of a device of any size to nearly it's full capacity (beyond 90%). But even a scale algorithm that changes the Capacity % bias from predominantly data, to predominantly metadata doesn't fix the problem. e.g. 95% Capacity per df, with a heavy metadata usage of the file system. Further metadata heavy writes might mean you're actually at 99% Capacity, whereas with minimal metadata writes might mean you're at 92% capacity. So which is correct to report? It depends on future usage, which is unknown. Small problem. Chris Murphy -- devel mailing list devel@lists.fedoraproject.org https://admin.fedoraproject.org/mailman/listinfo/devel
