Abstract: According to the migratory pattern means that the accessing processor initiates two separate requests to obtain first read and then write permission in invalidation-based protocol, this paper proposed adaptive protocol which uses the token number and the writer or reader of data to recognize the migratory pattern. While the data is in migratory pattern, the requestor’s state changes to MG state which can avoid the write request in migratory access. It effectively eliminates invalidation in migratory pattern. The adaptive protocol gets the ownership when reading the sharing data, and thus avoids some write misses. The results show that the adaptive protocol reduces the miss latency by an average of 5%, and the network traffic by an average of 9%.  

Key words: access pattern, migratory, invalidation, adaptive protocol