Author: cnauroth
Date: Mon Sep 16 05:35:25 2013
New Revision: 1523543
URL: http://svn.apache.org/r1523543
Log:
HDFS-5197. Document dfs.cachereport.intervalMsec in hdfs-default.xml.
Contributed by Chris Nauroth.
Modified:
hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/CHANGES-HDFS-4949.txt
hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
Modified:
hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/CHANGES-HDFS-4949.txt
URL:
http://svn.apache.org/viewvc/hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/CHANGES-HDFS-4949.txt?rev=1523543&r1=1523542&r2=1523543&view=diff
==============================================================================
---
hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/CHANGES-HDFS-4949.txt
(original)
+++
hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/CHANGES-HDFS-4949.txt
Mon Sep 16 05:35:25 2013
@@ -36,6 +36,9 @@ HDFS-4949 (Unreleased)
HDFS-5053. NameNode should invoke DataNode APIs to coordinate caching.
(Andrew Wang)
+ HDFS-5197. Document dfs.cachereport.intervalMsec in hdfs-default.xml.
+ (cnauroth)
+
OPTIMIZATIONS
BUG FIXES
Modified:
hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
URL:
http://svn.apache.org/viewvc/hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml?rev=1523543&r1=1523542&r2=1523543&view=diff
==============================================================================
---
hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
(original)
+++
hadoop/common/branches/HDFS-4949/hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml
Mon Sep 16 05:35:25 2013
@@ -1420,6 +1420,17 @@
</property>
<property>
+ <name>dfs.namenode.caching.enabled</name>
+ <value>false</value>
+ <description>
+ Set to true to enable block caching. This flag enables the NameNode to
+ maintain a mapping of cached blocks to DataNodes via processing DataNode
+ cache reports. Based on these reports and addition and removal of caching
+ directives, the NameNode will schedule caching and uncaching work.
+ </description>
+</property>
+
+<property>
<name>dfs.datanode.max.locked.memory</name>
<value>0</value>
<description>
@@ -1428,7 +1439,10 @@
(RLIMIT_MEMLOCK) must be set to at least this value, else the datanode
will abort on startup.
- By default, this parameter set to 0, which disables in-memory caching.
+ By default, this parameter is set to 0, which disables in-memory caching.
+
+ If the native libraries are not available to the DataNode, this
+ configuration has no effect.
</description>
</property>
@@ -1442,4 +1456,21 @@
</description>
</property>
+<property>
+ <name>dfs.cachereport.intervalMsec</name>
+ <value>10000</value>
+ <description>
+ Determines cache reporting interval in milliseconds. After this amount of
+ time, the DataNode sends a full report of its cache state to the NameNode.
+ The NameNode uses the cache report to update its map of cached blocks to
+ DataNode locations.
+
+ This configuration has no effect if in-memory caching has been disabled by
+ setting dfs.datanode.max.locked.memory to 0 (which is the default).
+
+ If the native libraries are not available to the DataNode, this
+ configuration has no effect.
+ </description>
+</property>
+
</configuration>
