private void loadQuerySampleThroughput(TrimProperties properties) throws IOException {
    String querySamplingRateLimitNumber =
        properties.getProperty(
            "query_sample_throughput_bytes_per_sec",
            ConfigurationFileUtils.getConfigurationDefaultValue(
                "query_sample_throughput_bytes_per_sec"));
    if (querySamplingRateLimitNumber != null) {
      try {
        int rateLimit = Integer.parseInt(querySamplingRateLimitNumber);
        commonDescriptor.getConfig().setQuerySamplingRateLimit(rateLimit);
      } catch (Exception e) {
        LOGGER.warn(
            "Failed to parse query_sample_throughput_bytes_per_sec {} to integer",
            querySamplingRateLimitNumber);
      }
    }
  }
load a property file and set TsfileDBConfig variables.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBDescriptor.java