presto-main/src/main/java/io/prestosql/operator/ExchangeClient.java/ExchangeClient/ExchangeClient
class ExchangeClient:    public ExchangeClient(
            DataSize bufferCapacity,
            DataSize maxResponseSize,
            int concurrentRequestMultiplier,
            Duration maxErrorDuration,
            boolean acknowledgePages,
            HttpClient httpClient,
            ScheduledExecutorService scheduler,
            LocalMemoryContext systemMemoryContext,
            Executor pageBufferClientCallbackExecutor)
    {
        this.bufferCapacity = bufferCapacity.toBytes();
        this.maxResponseSize = maxResponseSize;
        this.concurrentRequestMultiplier = concurrentRequestMultiplier;
        this.maxErrorDuration = maxErrorDuration;
        this.acknowledgePages = acknowledgePages;
        this.httpClient = httpClient;
        this.scheduler = scheduler;
        this.systemMemoryContext = systemMemoryContext;
        this.maxBufferRetainedSizeInBytes = Long.MIN_VALUE;
        this.pageBufferClientCallbackExecutor = requireNonNull(pageBufferClientCallbackExecutor, "pageBufferClientCallbackExecutor is null");
    }