diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRegionObserverScannerOpenHook.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRegionObserverScannerOpenHook.java
index 84600a9c49c..376c38b2116 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRegionObserverScannerOpenHook.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestRegionObserverScannerOpenHook.java
@@ -26,8 +26,10 @@ import java.io.IOException;
 import java.util.Collections;
 import java.util.List;
 import java.util.NavigableSet;
+import java.util.concurrent.CountDownLatch;
 
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.Coprocessor;
@@ -53,9 +55,12 @@ import org.apache.hadoop.hbase.regionserver.HStore;
 import org.apache.hadoop.hbase.regionserver.InternalScanner;
 import org.apache.hadoop.hbase.regionserver.KeyValueScanner;
 import org.apache.hadoop.hbase.regionserver.RegionCoprocessorHost;
+import org.apache.hadoop.hbase.regionserver.RegionServerServices;
 import org.apache.hadoop.hbase.regionserver.ScanType;
 import org.apache.hadoop.hbase.regionserver.Store;
 import org.apache.hadoop.hbase.regionserver.StoreScanner;
+import org.apache.hadoop.hbase.regionserver.compactions.CompactionContext;
+import org.apache.hadoop.hbase.regionserver.wal.HLog;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
@@ -203,6 +208,31 @@ public class TestRegionObserverScannerOpenHook {
           + r, r.listCells());
   }
 
+  /*
+   * Custom HRegion which uses CountDownLatch to signal the completion of compaction
+   */
+  public static class CompactionCompletionNotifyingRegion extends HRegion {
+    private static volatile CountDownLatch compactionStateChangeLatch = null;
+    
+    @SuppressWarnings("deprecation")
+    public CompactionCompletionNotifyingRegion(Path tableDir, HLog log,
+        FileSystem fs, Configuration confParam, HRegionInfo info,
+        HTableDescriptor htd, RegionServerServices rsServices) {
+      super(tableDir, log, fs, confParam, info, htd, rsServices);
+    }
+    
+    public CountDownLatch getCompactionStateChangeLatch() {
+      if (compactionStateChangeLatch == null) compactionStateChangeLatch = new CountDownLatch(1);
+      return compactionStateChangeLatch;
+    }
+    @Override
+    public boolean compact(CompactionContext compaction, Store store) throws IOException {
+      boolean ret = super.compact(compaction, store);
+      if (ret) compactionStateChangeLatch.countDown();
+      return ret;
+    }    
+  }
+  
   /**
    * Unfortunately, the easiest way to test this is to spin up a mini-cluster since we want to do
    * the usual compaction mechanism on the region, rather than going through the backdoor to the
@@ -212,6 +242,7 @@ public class TestRegionObserverScannerOpenHook {
   public void testRegionObserverCompactionTimeStacking() throws Exception {
     // setup a mini cluster so we can do a real compaction on a region
     Configuration conf = UTIL.getConfiguration();
+    conf.setClass(HConstants.REGION_IMPL, CompactionCompletionNotifyingRegion.class, HRegion.class);
     conf.setInt("hbase.hstore.compaction.min", 2);
     UTIL.startMiniCluster();
     String tableName = "testRegionObserverCompactionTimeStacking";
@@ -239,7 +270,9 @@ public class TestRegionObserverScannerOpenHook {
     assertEquals("More than 1 region serving test table with 1 row", 1, regions.size());
     HRegion region = regions.get(0);
     admin.flush(region.getRegionName());
-
+    CountDownLatch latch = ((CompactionCompletionNotifyingRegion)region)
+        .getCompactionStateChangeLatch();
+    
     // put another row and flush that too
     put = new Put(Bytes.toBytes("anotherrow"));
     put.add(A, A, A);
@@ -249,7 +282,7 @@ public class TestRegionObserverScannerOpenHook {
 
     // run a compaction, which normally would should get rid of the data
     // wait for the compaction checker to complete
-    Thread.sleep(1000);
+    latch.await();
     // check both rows to ensure that they aren't there
     Get get = new Get(ROW);
     Result r = table.get(get);