show blank spot rather than 0

files/grafana/daemon_metrics.json

@@ -45,7 +45,7 @@
       },
       "lines": true,
       "linewidth": 3,
-      "nullPointMode": "connected",
+      "nullPointMode": "null",
       "options": {
         "dataLinks": []
       },
@@ -143,7 +143,7 @@
       },
       "lines": false,
       "linewidth": 1,
-      "nullPointMode": "connected",
+      "nullPointMode": "null",
       "options": {
         "dataLinks": []
       },
@@ -236,7 +236,7 @@
       },
       "lines": false,
       "linewidth": 1,
-      "nullPointMode": "connected",
+      "nullPointMode": "null",
       "options": {
         "dataLinks": []
       },
@@ -328,7 +328,7 @@
       },
       "lines": true,
       "linewidth": 3,
-      "nullPointMode": "connected",
+      "nullPointMode": "null",
       "options": {
         "dataLinks": []
       },
@@ -525,7 +525,7 @@
         }
       ],
       "maxDataPoints": 100,
-      "nullPointMode": "connected",
+      "nullPointMode": "null",
       "nullText": null,
       "options": {},
       "postfix": "",