volution of the size of a the
   * corresponding root allocator (e.g. 'v8') over time.
   */
  function buildGlobalAllocatedMemoryChartSeries(globalMemoryDumps) {
    return buildMemoryChartSeries(globalMemoryDumps,
        extractGlobalMemoryDumpAllocatorSizes);
  }

  /**
   * Converts system memory counters in the model to a list of
   * {'name': trackName, 'series': ChartSeries}.
   */
  function buildSystemMemoryChartSeries(model) {
    if (model.kernel.counters === undefined) return;
    const memoryC