public void recordRepairTaskStartTimeIfLogFileEmpty(long repairTaskStartTime) throws IOException {
    if (logFile.length() != 0) {
      return;
    }
    String repairTaskStartTimeLog =
        String.format("%s %s\n", repairTaskStartTimeLogPrefix, repairTaskStartTime);
    logStream.write(repairTaskStartTimeLog.getBytes());
  }
Used for recovering StorageEngine or recovering stopped repair task
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/compaction/repair/RepairLogger.java