@Test
  public void testBatchingWhenException() throws Exception {
    runDropPartitions(23, 30, 0, oneException);
  }
Tests the number of calls to dropPartitions and the respective batch sizes when first call to
dropPartitions throws MetaException. The batch size should be reduced once by the
decayingFactor 2, iow after batch size is halved.

@throws Exception
ql/src/test/org/apache/hadoop/hive/ql/exec/TestMsckDropPartitionsInBatches.java