double queryFraction(double queryRateFraction) {
            double relativeQueryCost = 9; // How much more expensive are queries than writes? TODO: Measure
            double writeFraction = 1 - queryRateFraction;
            return queryRateFraction * relativeQueryCost / (queryRateFraction * relativeQueryCost + writeFraction);
        }
The estimated fraction of cpu usage which goes to processing queries vs. writes
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/autoscale/ClusterModel.java