@Override
  public String toString() {
    return "[CandidateInfo: Segments to compact " + segmentsToCompact + ", Cost " + cost + ", Benefit " + benefit
        + ", CostBenefitRatio " + costBenefitRatio + "]";
  }
@return the {@link List} of log segment names to compact
ambry-store/src/main/java/com/github/ambry/store/CostBenefitInfo.java