diff -ur v3/bk.py v4/bk.py
--- v3/bk.py	2018-05-05 09:35:39.000000000 +0900
+++ v4/bk.py	2018-06-07 09:50:49.000000000 +0900
@@ -68,12 +68,12 @@
 	db_d = db.get(d, {})
 
 	need_copy = lambda k, v: k not in db_d or not is_same(db_d.get(k), v)
-	items = filter( lambda kv: need_copy(kv[0], kv[1]), db_s.items() )
+	items = list( filter( lambda kv: need_copy(kv[0], kv[1]), db_s.items() ) )
 	if not items:
 		return ([], [])
 	(lst, _) = zip(*items)
 	lst = list(lst)
-	rm_lst = filter( lambda p: p in db_d, lst )
+	rm_lst = list( filter( lambda p: p in db_d, lst ) )
 	return (lst, rm_lst)
 
 def get_disk_free(path):
@@ -88,7 +88,7 @@
 	ut = 'KMGT'
 	i = 0
 	while v >= 1024 * 10 and i < 4:
-		v /= 1024
+		v = int( v / 1024 )
 		i += 1
 	return str(v) + ( ut[i-1] if i > 0 else '' )