YARN-4310. FairScheduler: Log skipping reservation messages at DEBUG level (asuresh)

(cherry picked from commit 58d1df585c2b8a4d2f78ae30726f07b4c6a94731)

hadoop-yarn-project/CHANGES.txt

@@ -497,6 +497,8 @@ Release 2.8.0 - UNRELEASED
     YARN-3216. Max-AM-Resource-Percentage should respect node labels. 
     (Sunil G via wangda)
 
+    YARN-4310. FairScheduler: Log skipping reservation messages at DEBUG level (asuresh)
+
   OPTIMIZATIONS
 
     YARN-3339. TestDockerContainerExecutor should pull a single image and not

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/FSAppAttempt.java

@@ -488,13 +488,15 @@ public class FSAppAttempt extends SchedulerApplicationAttempt
       if (existingReservations >= numAllowedReservations) {
         DecimalFormat df = new DecimalFormat();
         df.setMaximumFractionDigits(2);
-        LOG.info("Reservation Exceeds Allowed number of nodes:" +
-                " app_id=" + getApplicationId() +
-                " existingReservations=" + existingReservations +
-                " totalAvailableNodes=" + totalAvailNodes +
-                " reservableNodesRatio=" + df.format(
-                                        scheduler.getReservableNodesRatio()) +
-                " numAllowedReservations=" + numAllowedReservations);
+        if (LOG.isDebugEnabled()) {
+          LOG.debug("Reservation Exceeds Allowed number of nodes:" +
+                  " app_id=" + getApplicationId() +
+                  " existingReservations=" + existingReservations +
+                  " totalAvailableNodes=" + totalAvailNodes +
+                  " reservableNodesRatio=" + df.format(
+                                          scheduler.getReservableNodesRatio()) +
+                  " numAllowedReservations=" + numAllowedReservations);
+        }
         return true;
       }
     }