@Test
    void testMaxReaders() {
        assertThat(lmdbEnv.info().numReaders)
                .isEqualTo(0);
        IntStream.rangeClosed(1, 20).forEach(i -> {
            basicLmdbDb.put(buildKey(i), buildValue(i), false);

        });
        // Show that writes to the db do not effect the num readers high water mark
        assertThat(lmdbEnv.info().numReaders)
                .isEqualTo(0);

        basicLmdbDb.get(buildKey(1));

        assertThat(lmdbEnv.info().numReaders)
                .isEqualTo(1);
    }
This is more of a manual performance test for comparing the difference between
puts in integer order vs in random order. Also compares the impact of the INTEGER_KEY
dbi flag, which seems to slow things down a fair bit.
stroom-lmdb/src/test/java/stroom/lmdb/TestBasicLmdbDb.java