presto-main/src/main/java/io/prestosql/operator/ExchangeClientConfig.java/ExchangeClientConfig/setConcurrentRequestMultiplier
class ExchangeClientConfig:    @Config("exchange.concurrent-request-multiplier")
    public ExchangeClientConfig setConcurrentRequestMultiplier(int concurrentRequestMultiplier)
    {
        this.concurrentRequestMultiplier = concurrentRequestMultiplier;
        return this;
    }