Change format for drs imbalance to string

Author: vishesh92

plugins/metrics/src/main/java/org/apache/cloudstack/metrics/MetricsServiceImpl.java

@@ -789,7 +789,7 @@ public List<ClusterMetricsResponse> listClusterMetrics(Pair<List<ClusterResponse
 
             try {
                 Double imbalance = ClusterDrsAlgorithm.getClusterImbalance(clusterId, cpuList, memoryList, null);
-                metricsResponse.setDrsImbalance(imbalance.isNaN() ? null : imbalance);
+                metricsResponse.setDrsImbalance(imbalance.isNaN() ? null : String.format("%.2f%%", imbalance));
             } catch (ConfigurationException e) {
                 LOGGER.warn("Failed to get cluster imbalance for cluster " + clusterId, e);
             }

plugins/metrics/src/main/java/org/apache/cloudstack/response/ClusterMetricsResponse.java

@@ -96,7 +96,7 @@ public class ClusterMetricsResponse extends ClusterResponse implements HostMetri
 
     @SerializedName("drsimbalance")
     @Param(description = "DRS imbalance for the cluster")
-    private Double drsImbalance;
+    private String drsImbalance;
 
     public void setState(final String allocationState, final String managedState) {
         this.state = allocationState;
@@ -213,7 +213,11 @@ public void setMemoryAllocatedDisableThreshold(final Long memAllocated, final Lo
         }
     }
 
-    public void setDrsImbalance(Double drsImbalance) {
-        this.drsImbalance = drsImbalance;
+    public void setDrsImbalance(String drsImbalance) {
+        if (drsImbalance != null) {
+            this.drsImbalance = String.format("%.2f%%", drsImbalance);
+        } else {
+            this.drsImbalance = null;
+        }
     }
 }