From d2f4b7eb91b72d6bfa6d508aac5da3291556807c Mon Sep 17 00:00:00 2001
From: Jim Halfpenny <1987407+Jimvin@users.noreply.github.com>
Date: Tue, 27 May 2025 09:51:33 +0100
Subject: [PATCH] Added documentation for dfs.datanode.synconclose to
 hdfs-default.xml

---
 .../src/main/resources/hdfs-default.xml           | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
index 41dfbbca443fe..bcfdfa9334ffa 100755
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
@@ -1779,6 +1779,21 @@
   </description>
 </property>
 
+<property>
+  <name>dfs.datanode.synconclose</name>
+  <value>false</value>
+  <description>
+        If this configuration is enabled, the datanode will instruct the
+        operating system to sync data block files contents to disk when the
+        blockfile is closed.
+
+        This has the benefit of ensuring that data is written to disk
+        immeditately when a block is closed, avoiding the data being held
+        in the operating system cache. This can help data loss in the event
+        of a malfunction such as a power failure.
+  </description>
+</property>
+
 <property>
   <name>dfs.client.failover.max.attempts</name>
   <value>15</value>