From 370f4da168b218d9e43785f2eaf606fb7525ed75 Mon Sep 17 00:00:00 2001
From: Mingliang Liu <liuml07@apache.org>
Date: Fri, 3 Mar 2017 18:47:13 -0800
Subject: [PATCH] HDFS-11494. Log message when DN is not selected for block
 replication. Contributed by Yiqun Lin

---
 .../hdfs/server/blockmanagement/DatanodeDescriptor.java       | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeDescriptor.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeDescriptor.java
index 15af6ab1a7f..7b3e4e17d5d 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeDescriptor.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeDescriptor.java
@@ -687,6 +687,10 @@ public class DatanodeDescriptor extends DatanodeInfo {
       }
     }
     if (requiredSize > remaining - scheduledSize) {
+      LOG.debug(
+          "The node {} does not have enough {} space (required={},"
+          + " scheduled={}, remaining={}).",
+          this, t, requiredSize, scheduledSize, remaining);
       return null;
     }
     return storage;