bug fix: numpy mean nan warning

o_manager.py

@@ -120,6 +120,12 @@ class OManager:
                 value = float(value)
                 ping_tas.add(time, value)
 
+            def io_mean(x):
+                if len(x):
+                    return numpy.mean(x)
+                else:
+                    return numpy.nan
+
             def ping_mean(x):
                 x = numpy.array(x)
                 x = x[x > 0]
@@ -274,6 +280,10 @@ class OManager:
         # n_down = 2
         weights = []
         for i in self.instances:
+            if i["op"].status != RUNNING:
+                i["weight"] = 0
+                weights.append(i["weight"])
+                continue
             n_up = i["op"].n_up
             n_down = i["op"].n_down
             ping_stat = i["op"].get_ping_stat(lines=max(n_up, n_down))