@Test
  public void testStd() throws InterruptedException, ExecutionException {
    double avgSq =
      LongStream.range(0, COUNT).map(l -> l * l).reduce((l1, l2) -> l1 + l2).getAsLong()
        / (double) COUNT;
    double avg = (COUNT - 1) / 2.0;
    double std = Math.sqrt(avgSq - avg * avg);
    assertEquals(
      std, AsyncAggregationClient
        .std(TABLE, new LongColumnInterpreter(), new Scan().addColumn(CF, CQ)).get().doubleValue(),
      DELTA);
  }
Same as TestAsyncAggregationClient, except that {@link AsyncTableImpl} is involved in addition to
{@link RawAsyncTableImpl}. Exercises the code paths in {@link AsyncTableImpl#coprocessorService}.
hbase-endpoint/src/test/java/org/apache/hadoop/hbase/client/TestAsyncAggregationClientWithCallbackThreadPool.java