private Severity getMemoryRatioSeverity(double ratio) {
    return Severity.getSeverityDescending(
        ratio, memRatioLimits[0], memRatioLimits[1], memRatioLimits[2], memRatioLimits[3]);
  }
This heuristic deals with the efficiency of container size
app/com/linkedin/drelephant/mapreduce/heuristics/GenericMemoryHeuristic.java