HDFS-5853. Add "hadoop.user.group.metrics.percentiles.intervals" to hdfs-default.xml (aajisaka)

(cherry picked from commit aa55fd3096442f186aebc5a767d7e271b7224b51)

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -390,6 +390,9 @@ Release 2.7.0 - UNRELEASED
     HDFS-7685. Document dfs.namenode.heartbeat.recheck-interval in
     hdfs-default.xml. (Kai Sasaki via aajisaka)
 
+    HDFS-5853. Add "hadoop.user.group.metrics.percentiles.intervals" to
+    hdfs-default.xml. (aajisaka)
+
   OPTIMIZATIONS
 
     HDFS-7454. Reduce memory footprint for AclEntries in NameNode.

hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml

@@ -1508,6 +1508,17 @@
   </description>
 </property>
 
+<property>
+  <name>hadoop.user.group.metrics.percentiles.intervals</name>
+  <value></value>
+  <description>
+    A comma-separated list of the granularity in seconds for the metrics
+    which describe the 50/75/90/95/99th percentile latency for group resolution
+    in milliseconds.
+    By default, percentile latency metrics are disabled.
+  </description>
+</property>
+
 <property>
   <name>dfs.encrypt.data.transfer</name>
   <value>false</value>