HDFS-4618. Default transaction interval for checkpoints is too low. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1461783 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -373,6 +373,8 @@ Release 2.0.5-beta - UNRELEASED
 
     HDFS-4621. Additional logging to help diagnose slow QJM syncs. (todd)
 
+    HDFS-4618. Default transaction interval for checkpoints is too low. (todd)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java

@@ -122,7 +122,7 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
   public static final String  DFS_NAMENODE_CHECKPOINT_PERIOD_KEY = "dfs.namenode.checkpoint.period";
   public static final long    DFS_NAMENODE_CHECKPOINT_PERIOD_DEFAULT = 3600;
   public static final String  DFS_NAMENODE_CHECKPOINT_TXNS_KEY = "dfs.namenode.checkpoint.txns";
-  public static final long    DFS_NAMENODE_CHECKPOINT_TXNS_DEFAULT = 40000;
+  public static final long    DFS_NAMENODE_CHECKPOINT_TXNS_DEFAULT = 1000000;
   public static final String  DFS_NAMENODE_CHECKPOINT_MAX_RETRIES_KEY = "dfs.namenode.checkpoint.max-retries";
   public static final int     DFS_NAMENODE_CHECKPOINT_MAX_RETRIES_DEFAULT = 3;
   public static final String  DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY = "dfs.namenode.heartbeat.recheck-interval";

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

@@ -635,7 +635,7 @@
 
 <property>
   <name>dfs.namenode.checkpoint.txns</name>
-  <value>40000</value>
+  <value>1000000</value>
   <description>The Secondary NameNode or CheckpointNode will create a checkpoint
   of the namespace every 'dfs.namenode.checkpoint.txns' transactions, regardless
   of whether 'dfs.namenode.checkpoint.period' has expired.

hadoop-hdfs-project/hadoop-hdfs/src/site/apt/HdfsUserGuide.apt.vm

@@ -193,7 +193,7 @@ HDFS Users Guide
      * <<<dfs.namenode.checkpoint.period>>>, set to 1 hour by default, specifies
        the maximum delay between two consecutive checkpoints, and
 
-     * <<<dfs.namenode.checkpoint.txns>>>, set to 40000 default, defines the
+     * <<<dfs.namenode.checkpoint.txns>>>, set to 1 million by default, defines the
        number of uncheckpointed transactions on the NameNode which will
        force an urgent checkpoint, even if the checkpoint period has not
        been reached.
@@ -232,7 +232,7 @@ HDFS Users Guide
      * <<<dfs.namenode.checkpoint.period>>>, set to 1 hour by default, specifies
        the maximum delay between two consecutive checkpoints
 
-     * <<<dfs.namenode.checkpoint.txns>>>, set to 40000 default, defines the
+     * <<<dfs.namenode.checkpoint.txns>>>, set to 1 million by default, defines the
        number of uncheckpointed transactions on the NameNode which will
        force an urgent checkpoint, even if the checkpoint period has not
        been reached.