private static Statistics statistics(final RocksRawKVStore rocksRawKVStore) {
        return statisticsGetter.get(rocksRawKVStore);
    }
DB implementations can export properties about their state
via this method.
jraft-rheakv/rheakv-core/src/main/java/com/alipay/sofa/jraft/rhea/rocks/support/RocksStatistics.java