code: public double calculateInitialTotalCost(final List<ServerHolder> serverHolders)
    {
      double cost = 0;
      for (ServerHolder server : serverHolders) {
        Iterable<DataSegment> segments = server.getServer().getLazyAllSegments();
        for (DataSegment s : segments) {
          cost += computeJointSegmentsCost(s, segments);
        }
      }
      return cost;
    }
docs: Calculates the initial cost of the Druid segment configuration.
  
  @param serverHolders A list of ServerHolders for a particular tier.
  
  @return The initial cost of the Druid tier.