The packet generator (pktgen) is a fundamental module of the majority of software testers used to benchmark network protocols and functions.The high performance of the pktgen is an important feature of Future Intet Testbeds,and DPDK is a network packet accelerated platform,so we can use DPDK to improve performance.Meanwhile,green computing is advocated for in the future of the intet.Most existing efforts have contributed to improving either performance or accuracy.We,however,shifted the focus to energy-efficiency.We find that high performance comes at the cost of high energy consumption.Therefore,we started from a widely used high performance schema,deeply studying the multi-core platform,especially in terms of parallelism,core allocation,and frequency controlling.On this basis,we proposed an AFfinity-oriented Fine-grained CONtrolling (AFFCON) mechanism in order to improve energy efficiency with desirable performance.As clearly demonstrated through a series of evaluative experiments,our proposal can reduce CPU power consumption by up to 11％ while maintaining throughput at the line rate.