docs: private static synchronized Datum generateCurrentSample() {
          // Code used to fake system statistics by tests
          if (testStatsProducer!=null) {
              return testStatsProducer.getCurrentStatsData();
          }
  
          // get this info once
          if (!initialized) initialize();
  
          long rss = -1;
          switch (mode) {
          case MACOSX_NATIVE:
              rss = ExecutionEngine.nativeGetRSS();
              break;
          case PROCFS:
              rss = getRSSFromProcFS();
              break;
          case PS:
              rss = PSScraper.getPSData(pid).rss;
              break;
          }
  
          // create a new Datum which adds java stats
          Datum d = new Datum(rss);
          return d;
      }