diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/RoundRobinVolumeChoosingPolicy.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/RoundRobinVolumeChoosingPolicy.java
index 2d924c0236..0f23e47096 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/RoundRobinVolumeChoosingPolicy.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/fsdataset/RoundRobinVolumeChoosingPolicy.java
@@ -96,6 +96,10 @@ public class RoundRobinVolumeChoosingPolicy<V extends FsVolumeSpi>
         throw new DiskOutOfSpaceException("Out of space: "
             + "The volume with the most available space (=" + maxAvailable
             + " B) is less than the block size (=" + blockSize + " B).");
+      } else {
+        LOG.warn("The volume[{}] with the available space (={} B) is "
+            + "less than the block size (={} B).", volume.getBaseURI(),
+            availableVolumeSize, blockSize);
       }
     }
   }