diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/Util.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/Util.java
index e9f9bfb830c..85bd490efe6 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/Util.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/common/Util.java
@@ -285,7 +285,7 @@ public final class Util {
         fos.getChannel().force(true);
         fos.close();
         double writeSec = Math.max(((float)
-            (flushStartTime - Time.monotonicNow())) / 1000.0, 0.001);
+            (Time.monotonicNow() - flushStartTime)) / 1000.0, 0.001);
         xferCombined += writeSec;
         xferStats.append(String
             .format(" Synchronous (fsync) write to disk of " +