open-falcon · wolfhong · Jun 21, 2018 · Jun 22, 2018 · Jun 22, 2018 · Jun 22, 2018
diff --git a/README.md b/README.md
@@ -4,8 +4,8 @@
 
 # Installation
 
-### Download prebuild version of grafana official site
-[https://grafana.com/grafana/download](https://grafana.com/grafana/download) `Grafana v4.2`
+### Download prebuild version of grafana on official site
+[https://grafana.com/grafana/download](https://grafana.com/grafana/download) `Grafana v3.0 or newer(test passed on v5.0.3)`
 
 **or you can install grafana via homebrerw:**
 
@@ -25,11 +25,19 @@ git clone https://github.com/open-falcon/grafana-openfalcon-datasource
 {GRAFANA_PATH_Installed}/bin/grafana-server
 ```
 
-## After Installation
+If you have started grafana-server, you have to restart it after installing plugins.
+
+# After Installation
 If the installation is successful, Open-Falcon datasource would be shown as follow:
 ![](img/openfalcon_datasource.png)
 
-## How to Set up datasource
+# How to Set up datasource
 * the backend services is provide by [falcon-plus](https://github.com/open-falcon/falcon-plus/tree/master/modules/api).
 
 ![](img/setup_grafana.png)
+
+# Work with variables
+
+When you select metrics, you can use variables if you "Toggle Edit Mode", e.g. `$host#mem#memfree#percent` is ok.
+
+![](img/grafana_with_variables.png)
diff --git a/datasource.js b/datasource.js
diff --git a/img/grafana_with_variables.png b/img/grafana_with_variables.png
diff --git a/img/openfalcon_datasource.png b/img/openfalcon_datasource.png
diff --git a/lexer.js b/lexer.js
diff --git a/parser.js b/parser.js
diff --git a/query_ctrl.js b/query_ctrl.js