presto-main/src/main/java/io/prestosql/cost/CostCalculatorUsingExchanges.java/CostEstimator/visitFilter
class CostEstimator:        @Override
        public PlanCostEstimate visitFilter(FilterNode node, Void context)
        {
            LocalCostEstimate localCost = LocalCostEstimate.ofCpu(getStats(node.getSource()).getOutputSizeInBytes(node.getOutputSymbols(), types));
            return costForStreaming(node, localCost);
        }