Abstract: Single-core processors' performance has been behind the times. Many-core processors are recognized as a promising approach to packet forwarding in a router due to their powerful parallel processing. However, how to utilize the lots of cores in many-core processors to improve the system's parallel performance is a problem. Many-core based packet processing systems use a pipeline architecture, where each stage has a different execution time and requires a different number of CPU cores. Recently proposed EQUI is an equal core allocation scheme for packet processing, which allocates a same number of cores to each job. However, such scheme suffers from the wasting core resources, limiting packet processing performance. To address this issue, this paper proposes an optimized core allocation scheme. This scheme first partitions the task of packet processing into multiple jobs, and then proportionally allocates a proper number of cores to each job according to its execution time. Experimental results show that the new scheme improve 20% packet forwarding rate compared with EQUI.