Title :
Improving Token Coherence by Multicast Coherence Messages
Author :
Cuesta, Blas ; Robles, Antonio ; Duato, Jose
Author_Institution :
Univ. Polytech. de Valencia, Valencia
Abstract :
Token coherence is a cache coherence protocol that joins the main advantages of traditional protocols. However, unlike them, token coherence does not handle messages in order, which may lead to races, causing some cache misses not to be solved. To assure their completion, an inefficient mechanism named persistent requests is used. Recently we have proposed the priority request mechanism to efficiently handle races. As acknowledgements are not required, a single node can solve several misses for the same memory block at the same time. When solving a lot of misses, the node may become a bottleneck. To avoid it, in this work we propose the multicast coherence message, which allows to simultaneously resolve several misses by using only one response message. It reduces the network traffic and the average response latency, improving significantly the overall performance.
Keywords :
cache storage; multicast protocols; routing protocols; average response latency; cache coherence protocol; multicast coherence messages; network traffic; priority request mechanism; token coherence; Computer networks; Concurrent computing; Delay; Distributed computing; Mechanical factors; Multicast protocols; Telecommunication traffic; Turning; Cache coherence; SMP; Token Cohence; multicast; protocol races;
Conference_Titel :
Parallel, Distributed and Network-Based Processing, 2008. PDP 2008. 16th Euromicro Conference on
Conference_Location :
Toulouse
Print_ISBN :
978-0-7695-3089-5
DOI :
10.1109/PDP.2008.36