On Sun, Mar 1, 2020 at 8:45 PM Rich Rauenzahn <rrauenza@xxxxxxxxx> wrote: > > On Sun, Mar 1, 2020 at 6:38 PM Rich Rauenzahn <rrauenza@xxxxxxxxx> wrote: > > ...but that's what I'd expect the balance to do? If Block (Chunk?) A > > is on, say device 1 (4TB) and device 2 (2TB), why wouldn't it move > > Block A to the new drive from device 1 or 2 in order to free up space > > and balance/spread out usage across the drives? Is that not what > > balance's purpose is? Or is free space required on 1 or 2 in order > > to move the allocation to the new drive? > > Am I just not taking COW into account? It rewrites the chunk to > reallocate so needs two destinations? There is no "move"? Correct. The block group is a single unit, there isn't (yet) a short cut to COW just one of the two copies to another device. -- Chris Murphy
