HBASE-440 Add optional log roll interval so that log files are garbage collected

git-svn-id: https://svn.apache.org/repos/asf/hadoop/hbase/trunk@627152 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -44,6 +44,8 @@ Hbase Change Log
    HBASE-436   website: http://hadoop.apache.org/hbase
    HBASE-417   Factor TableOperation and subclasses into separate files from
                HMaster (Bryan Duxbury via Stack)
+   HBASE-440   Add optional log roll interval so that log files are garbage
+               collected
 
 
 Branch 0.1

conf/hbase-default.xml

@@ -155,6 +155,16 @@
     Default: 30 minutes (in miliseconds)
     </description>
   </property>
+  <property>
+    <name>hbase.regionserver.optionallogrollinterval</name>
+    <value>1800000</value>
+    <description>
+    Amount of time to wait since the last time a the region server's log was
+    rolled before invoking an optional log roll (An optional log roll is a
+    one in which the log does not contain hbase.regionserver.maxlogentries).
+    Default: 30 minutes (in miliseconds)
+    </description>
+  </property>
   <property>
     <name>hbase.hregion.memcache.flush.size</name>
     <value>67108864</value>

src/java/org/apache/hadoop/hbase/HRegionServer.java

@@ -508,12 +508,17 @@ public class HRegionServer implements HConstants, HRegionInterface, Runnable {
   /** Runs periodically to determine if the HLog should be rolled */
   class LogRoller extends Thread implements LogRollListener {
     private final Integer rollLock = new Integer(0);
+    private final long optionalLogRollInterval;
+    private long lastLogRollTime;
     private volatile boolean rollLog;
     
     /** constructor */
     public LogRoller() {
       super();
+      this.optionalLogRollInterval = conf.getLong(
+          "hbase.regionserver.optionallogrollinterval", 30L * 60L * 1000L);
       this.rollLog = false;
+      lastLogRollTime = System.currentTimeMillis();
     }
  
     /** {@inheritDoc} */
@@ -521,6 +526,11 @@ public class HRegionServer implements HConstants, HRegionInterface, Runnable {
     public void run() {
       while (!stopRequested.get()) {
         while (!rollLog && !stopRequested.get()) {
+          long now = System.currentTimeMillis();
+          if (this.lastLogRollTime + this.optionalLogRollInterval <= now) {
+            rollLog = true;
+            this.lastLogRollTime = now;
+          } else {
             synchronized (rollLock) {
               try {
                 rollLock.wait(threadWakeFrequency);
@@ -530,6 +540,7 @@ public class HRegionServer implements HConstants, HRegionInterface, Runnable {
               }
             }
           }
+        }
         if (!rollLog) {
           // There's only two reasons to break out of the while loop.
           // 1. Log roll requested