public double avgBatchDurationMs() {
        if (totalBatches == 0) {
            return -1;
        }
        return 1.0 * TimeUnit.NANOSECONDS.toMillis(totalBatchDurationsNs) / totalBatches;
    }
Holds the results of a ZK to KRaft metadata migration. The {@link #toString()} can be used to provide a
human-readable summary of the migration.
metadata/src/main/java/org/apache/kafka/metadata/migration/MigrationManifest.java