diff --git a/CHANGES b/CHANGES
index f1b7e6e509..f14e7b6b1d 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,5 +1,6 @@
 Tajo Change Log 
 
+
 Release 0.11.0 - unreleased
 
   NEW FEATURES
diff --git a/tajo-core/src/main/java/org/apache/tajo/engine/utils/ThreadUtil.java b/tajo-core/src/main/java/org/apache/tajo/engine/utils/ThreadUtil.java
deleted file mode 100644
index 23b1e5d24d..0000000000
--- a/tajo-core/src/main/java/org/apache/tajo/engine/utils/ThreadUtil.java
+++ /dev/null
@@ -1,149 +0,0 @@
-/**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.apache.tajo.engine.utils;
-
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.util.ReflectionUtils;
-
-import java.io.PrintWriter;
-import java.lang.Thread.UncaughtExceptionHandler;
-
-public class ThreadUtil {
-	protected static final Log LOG = LogFactory.getLog(ThreadUtil.class);
-
-	  /**
-	   * Utility method that sets name, daemon status and starts passed thread.
-	   * @param t thread to run
-	   * @return Returns the passed Thread <code>t</code>.
-	   */
-	  public static Thread setDaemonThreadRunning(final Thread t) {
-	    return setDaemonThreadRunning(t, t.getName());
-	  }
-
-	  /**
-	   * Utility method that sets name, daemon status and starts passed thread.
-	   * @param t thread to frob
-	   * @param name new name
-	   * @return Returns the passed Thread <code>t</code>.
-	   */
-	  public static Thread setDaemonThreadRunning(final Thread t,
-	    final String name) {
-	    return setDaemonThreadRunning(t, name, null);
-	  }
-
-	  /**
-	   * Utility method that sets name, daemon status and starts passed thread.
-	   * @param t thread to frob
-	   * @param name new name
-	   * @param handler A handler to set on the thread.  Pass null if want to
-	   * use default handler.
-	   * @return Returns the passed Thread <code>t</code>.
-	   */
-	  public static Thread setDaemonThreadRunning(final Thread t,
-	    final String name, final UncaughtExceptionHandler handler) {
-	    t.setName(name);
-	    if (handler != null) {
-	      t.setUncaughtExceptionHandler(handler);
-	    }
-	    t.setDaemon(true);
-	    t.start();
-	    return t;
-	  }
-
-	  /**
-	   * Shutdown passed thread using isAlive and join.
-	   * @param t Thread to shutdown
-	   */
-	  public static void shutdown(final Thread t) {
-	    shutdown(t, 0);
-	  }
-
-	  /**
-	   * Shutdown passed thread using isAlive and join.
-	   * @param joinwait Pass 0 if we're to wait forever.
-	   * @param t Thread to shutdown
-	   */
-	  public static void shutdown(final Thread t, final long joinwait) {
-	    if (t == null) return;
-	    while (t.isAlive()) {
-	      try {
-	        t.join(joinwait);
-	      } catch (InterruptedException e) {
-	        LOG.warn(t.getName() + "; joinwait=" + joinwait, e);
-	      }
-	    }
-	  }
-
-
-	  /**
-	   * @param t Waits on the passed thread to die dumping a threaddump every
-	   * minute while its up.
-	   * @throws InterruptedException
-	   */
-	  public static void threadDumpingIsAlive(final Thread t)
-	  throws InterruptedException {
-	    if (t == null) {
-	      return;
-	    }
-
-	    while (t.isAlive()) {
-	      t.join(60 * 1000);
-	      if (t.isAlive()) {
-	        ReflectionUtils.printThreadInfo(new PrintWriter(System.out),
-	            "Automatic Stack Trace every 60 seconds waiting on " +
-	            t.getName());
-	      }
-	    }
-	  }
-
-	  /**
-	   * @param millis How long to sleep for in milliseconds.
-	   */
-	  public static void sleep(int millis) {
-	    try {
-	      Thread.sleep(millis);
-	    } catch (InterruptedException e) {
-	      e.printStackTrace();
-	    }
-	  }
-
-	  /**
-	   * Sleeps for the given amount of time even if interrupted. Preserves
-	   * the interrupt status.
-	   * @param msToWait the amount of time to sleep in milliseconds
-	   */
-	  public static void sleepWithoutInterrupt(final long msToWait) {
-	    long timeMillis = System.currentTimeMillis();
-	    long endTime = timeMillis + msToWait;
-	    boolean interrupted = false;
-	    while (timeMillis < endTime) {
-	      try {
-	        Thread.sleep(endTime - timeMillis);
-	      } catch (InterruptedException ex) {
-	        interrupted = true;
-	      }
-	      timeMillis = System.currentTimeMillis();
-	    }
-
-	    if (interrupted) {
-	      Thread.currentThread().interrupt();
-	    }
-	  }
-}