bug fix

o_manager.py

@@ -88,7 +88,7 @@ class OManager:
         }
         return state
 
-    def get_stat(self, time_range=5, n_bins=200):
+    def get_stat(self, time_range=5, n_bins=60):
         stat = []
 
         now = datetime.now()
@@ -100,9 +100,9 @@ class OManager:
             io_tas = TimeSeriesAccumulator(
                 start_time=now-timedelta(minutes=time_range), end_time=now, n_bins=n_bins)
             for line in io_stat:
-                time, value = line.split(",")
+                time, value_down, value_up = line.split(",")
                 time = datetime.utcfromtimestamp(float(time))
-                value = float(value)
+                value = float(value_down)
                 if first_line:
                     first_line = False
                 else:
@@ -124,6 +124,8 @@ class OManager:
 
             def ping_rate(x):
                 x = numpy.array(x)
+                if len(x)==0:
+                    return numpy.nan
                 return numpy.count_nonzero(x > 0)/len(x)
 
             stat.append({
@@ -131,7 +133,13 @@ class OManager:
                 "ping_mean": ping_tas.get_f(ping_mean),
                 "ping_rate": ping_tas.get_f(ping_rate)
             })
-        return stat
+        if self.instances:
+            xs = [j.isoformat() for j in ping_tas.get_ts()]
+            return {
+                    "time": xs,
+                    "stat": stat
+                    }
+        return {}
 
     def generate_lb_cfg(self, load_balance_mode):
         lb_cfg_fp = os.path.join(