core/src/main/java/com/orientechnologies/orient/core/storage/impl/local/statistic/OSessionStoragePerformanceStatistic.java
public long getReadSpeedFromFileInPages(String componentName) {
    if (componentName == null)
      return performanceCountersHolder.getReadSpeedFromFileInPages();

    final PerformanceCountersHolder cHolder = countersByComponent.get(componentName);
    if (cHolder != null)
      return cHolder.getReadSpeedFromFileInPages();

    return -1;
  }
public long getReadSpeedFromFileInPages(String componentName) {
    if (componentName == null)
      return performanceCountersHolder.getReadSpeedFromFileInPages();

    final PerformanceCountersHolder cHolder = countersByComponent.get(componentName);
    if (cHolder != null)
      return cHolder.getReadSpeedFromFileInPages();

    return -1;
  }
Read speed of data from file system in pages for component name of which is passed as method argument. If null value is passed
then value for whole system will be returned. If data for component with passed in name does not exist then <code>-1</code>
will be returned.

@param componentName Name of component data of which should be returned. Name is case sensitive.

@return Read speed of data from file system in pages per second or value which is less than 0, which means that value cannot be
calculated.