fix on CHO test

Change-Id: Ib9a1fcd51c04f1492a7fb5f4cd9633df4a98d3a5
diff --git a/TestON/tests/CHOTestMonkey/CHOTestMonkey.params b/TestON/tests/CHOTestMonkey/CHOTestMonkey.params
index b1b9d0f..00afaf6 100644
--- a/TestON/tests/CHOTestMonkey/CHOTestMonkey.params
+++ b/TestON/tests/CHOTestMonkey/CHOTestMonkey.params
@@ -41,6 +41,10 @@
         <testDuration>86400</testDuration>
         <package>on</package>
     </TEST>
+    <GRAPH>
+        <nodeCluster>CHO</nodeCluster>
+        <builds>20</builds>
+    </GRAPH>
     <ENV>
         <cellName>choCell</cellName>
         <cellApps>drivers,openflow,proxyarp,events</cellApps>