94b78b
@@ -19,8 +19,6 @@
  */
 package org.apache.hadoop.hbase.master;
 
-import java.io.DataInput;
-import java.io.DataOutput;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Comparator;
@@ -39,7 +37,6 @@
import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.HRegionInfo;
 import org.apache.hadoop.hbase.HServerInfo;
-import org.apache.hadoop.io.Writable;
 
 /**
  * Makes decisions about the placement and movement of Regions across
@@ -131,8 +128,6 @@
public class LoadBalancer {
    */
   public List<RegionPlan> balanceCluster(
       Map<HServerInfo,List<HRegionInfo>> clusterState) {
-    LOG.debug("Running load balancer");
-
     long startTime = System.currentTimeMillis();
 
     // Make a map sorted by load and count regions
@@ -141,7 +136,7 @@
public class LoadBalancer {
           new HServerInfo.LoadComparator());
     int numServers = clusterState.size();
     if (numServers == 0) {
-      LOG.debug("numServers=0 so nothing to balance");
+      LOG.debug("numServers=0 so skipping load balancing");
       return null;
     }
     int numRegions = 0;
@@ -240,13 +235,14 @@
public class LoadBalancer {
     // Either more regions to assign out or servers that are still underloaded
 
     // If we need more to fill min, grab one from each most loaded until enough
-    if(neededRegions != 0) {
+    if (neededRegions != 0) {
       // Walk down most loaded, grabbing one from each until we get enough
       for(Map.Entry<HServerInfo, List<HRegionInfo>> server :
         serversByLoad.descendingMap().entrySet()) {
         BalanceInfo balanceInfo = serverBalanceInfo.get(server.getKey());
         int idx =
           balanceInfo == null ? 0 : balanceInfo.getNextRegionForUnload();
+        if (idx >= server.getValue().size()) break;
         HRegionInfo region = server.getValue().get(idx);
         if (region.isMetaRegion()) continue; // Don't move meta regions.
         regionsToMove.add(new RegionPlan(region, server.getKey(), null));
