private long getChunkSize(Chunk chunk) {
    return (long) chunk.getHeader().getSerializedSize() + chunk.getHeader().getDataSize();
  }
This function execute the compaction of a single time series. Notice, the result of single
series compaction may contain more than one chunk.

@throws IOException if io errors occurred
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/compaction/execute/utils/executor/readchunk/SingleSeriesCompactionExecutor.java