shouldn't we prune the files before writing the new one? In the case where you have run out of disk space already this won't help (yea its probably not the fish's fault in this case but if your looking for corner cases). [`riak_core_ring_manager`](https://github.com/basho/riak_core/blob/develop/src/riak_core_ring_manager.erl#L628-L629) which does something similar prunes prior to writing.