> On Sun, Dec 07, 2014 at 10:20:27AM -0800, ashf...@whisperpc.com wrote: > [snip] >> > 3) From what I gathered it is planned to allow different raid / >> > redundancy levels for different subvolumes. BTRFS can´t know >> > beforehand where applications request to save future data, i.e. >> > in which subvolume. >> >> Same as above. >> >> If a user will be requesting to use a specific subvolume, it is up to >> them >> to verify that adequate free space exists there, or handle the >> exception. > > OK, so let's say I've got a filesystem with 100 GiB of unallocated > space. I have two subvolumes, one configured for RAID-1 and one > configured for single storage. > > What number should be shown in the free output of df? > > 100 GiB? But I can only write 50 GiB to the RAID-1 subvolume before > it runs out of space. > > 50 GiB? I can get twice that much on the single subvolume. > > *Any* value shown here is going to be inaccurate, and whatever way > round we show it, someone will complain.
As an example, let's assume that the file-system is mounted as /data, with a non-mirrored subvolume of /data/1 and a mirrored subvolume of /data/2. A df should should 100GiB free in both /data and /data/1, and 50GiB free in /data/2. Peter Ashford -- 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
