presto-benchmark/src/main/java/io/prestosql/benchmark/HashBuildBenchmark.java/HashBuildBenchmark/createDrivers
class HashBuildBenchmark:    @Override
    protected List<Driver> createDrivers(TaskContext taskContext)
    {
        // hash build
        List<Type> ordersTypes = getColumnTypes("orders", "orderkey", "totalprice");
        OperatorFactory ordersTableScan = createTableScanOperator(0, new PlanNodeId("test"), "orders", "orderkey", "totalprice");
        JoinBridgeManager<PartitionedLookupSourceFactory> lookupSourceFactoryManager = JoinBridgeManager.lookupAllAtOnce(new PartitionedLookupSourceFactory(
                ordersTypes,
                ImmutableList.of(0, 1).stream()
                        .map(ordersTypes::get)
                        .collect(toImmutableList()),
                Ints.asList(0).stream()
                        .map(ordersTypes::get)
                        .collect(toImmutableList()),
                1,
                requireNonNull(ImmutableMap.of(), "layout is null"),
                false));
        HashBuilderOperatorFactory hashBuilder = new HashBuilderOperatorFactory(
                1,
                new PlanNodeId("test"),
                lookupSourceFactoryManager,
                ImmutableList.of(0, 1),
                Ints.asList(0),
                OptionalInt.empty(),
                Optional.empty(),
                Optional.empty(),
                ImmutableList.of(),
                1_500_000,
                new PagesIndex.TestingFactory(false),
                false,
                SingleStreamSpillerFactory.unsupportedSingleStreamSpillerFactory());
        DriverFactory hashBuildDriverFactory = new DriverFactory(0, true, true, ImmutableList.of(ordersTableScan, hashBuilder), OptionalInt.empty(), UNGROUPED_EXECUTION);

        // empty join so build finishes
        ImmutableList.Builder<OperatorFactory> joinDriversBuilder = ImmutableList.builder();
        joinDriversBuilder.add(new ValuesOperatorFactory(0, new PlanNodeId("values"), ImmutableList.of()));
        OperatorFactory joinOperator = LOOKUP_JOIN_OPERATORS.innerJoin(
                2,
                new PlanNodeId("test"),
                lookupSourceFactoryManager,
                ImmutableList.of(BIGINT),
                Ints.asList(0),
                OptionalInt.empty(),
                Optional.empty(),
                OptionalInt.empty(),
                unsupportedPartitioningSpillerFactory());
        joinDriversBuilder.add(joinOperator);
        joinDriversBuilder.add(new NullOutputOperatorFactory(3, new PlanNodeId("test")));
        DriverFactory joinDriverFactory = new DriverFactory(1, true, true, joinDriversBuilder.build(), OptionalInt.empty(), UNGROUPED_EXECUTION);

        Driver hashBuildDriver = hashBuildDriverFactory.createDriver(taskContext.addPipelineContext(0, true, true, false).addDriverContext());
        hashBuildDriverFactory.noMoreDrivers();
        Driver joinDriver = joinDriverFactory.createDriver(taskContext.addPipelineContext(1, true, true, false).addDriverContext());
        joinDriverFactory.noMoreDrivers();

        return ImmutableList.of(hashBuildDriver, joinDriver);
    }