Abstract: The shared last level cache(LLC) of CMP often uses a static address mapping method. This method may map some processor's temporary private data to other processor's last level cache. The processor needs longer access latency on these data than on the data mapped to local. This paper proposed a combined method of dynamic and static address mapping. The method can map most temporary data to their accessing processor's cache, so that these data's access latency can be reduced to loca lLLC access latency and the power and bandwidth of interconnection wasted for these data are saved. The experiment results show that the combined method of static and dynamic address mapping used in a CMP with a ring interconnection and SOR cache coherence protocol can obtain average performance increase of 9%，and the maximum is 38%.

Key words: CMP, Shared last level cache, Address mapping method, Ring, SOR cache coherence protocol