void recordAggregatedMetrics(int bytes, int records) {
        metricAggregator.record(partition.topicPartition(), bytes, records);
    }
After each partition is parsed, we update the current metric totals with the total bytes
and number of records parsed. After all partitions have reported, we write the metric.
clients/src/main/java/org/apache/kafka/clients/consumer/internals/ShareCompletedFetch.java