presto-main/src/main/java/io/prestosql/operator/exchange/PassthroughExchanger.java/PassthroughExchanger/PassthroughExchanger
class PassthroughExchanger:    public PassthroughExchanger(LocalExchangeSource localExchangeSource, long bufferMaxMemory, LongConsumer memoryTracker)
    {
        this.localExchangeSource = requireNonNull(localExchangeSource, "localExchangeSource is null");
        this.bufferMemoryManager = new LocalExchangeMemoryManager(bufferMaxMemory);
        this.memoryTracker = requireNonNull(memoryTracker, "memoryTracker is null");
    }