@Test
public void checkpointEveryTenPartitions() {

    RangeComparator comparator = comparator(context(0L, 100L));
    comparator.compare(keys(LongStream.range(0, 25).toArray()),
                       keys(LongStream.range(0, 25).toArray()),
                       this::alwaysMatch);
    assertReported(9, RangeStats.withValues(10, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L), journal);
    assertReported(19, RangeStats.withValues(20, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L), journal);
    assertEquals(2, journal.keySet().size());
}