rSorted[i + 1].start -
            tasksInClusterSorted[i].end;
        if (durationBetweenTasks >= FCI_MIN_CLUSTER_SEPARATION_MS) {
          throw new Error('Internal Error: Tasks in a TaskCluster cannot be ' +
                          'more than ' + FCI_MIN_CLUSTER_SEPARATION_MS +
                          ' miliseconds apart');
        }

        // Ideally the condition below should be durationBetweenTasks < 0, but
        // sometimes, for rounding errors, the end time of one task may very
        //