@Test
  public void testFencingAroundCompaction() throws Exception {
    for (MemoryCompactionPolicy policy : MemoryCompactionPolicy.values()) {
      doTest(BlockCompactionsInPrepRegion.class, policy);
    }
  }
Test that puts up a regionserver, starts a compaction on a loaded region but holds the
compaction until after we have killed the server and the region has come up on a new
regionserver altogether. This fakes the double assignment case where region in one location
changes the files out from underneath a region being served elsewhere.
hbase-server/src/test/java/org/apache/hadoop/hbase/TestIOFencing.java