code: private void rebuildAggRow(GraphRowSimple row, long time, long duration) {
          long key = row.getHigherKey(lastAggUpdateTime - duration - 1);
          while (key < time && key != -1) {
              GraphPanelChartSimpleElement elt = (GraphPanelChartSimpleElement) row.getElement(key);
              elt.add(getAllThreadCount(key));
  
              Long nextKey = row.getHigherKey(key);
              if (nextKey != null) {
                  key = nextKey;
              } else {
                  key = -1;
              }
          }
      }
docs: perf fix: only process elements between time and last processed - sampler duration