Performance Evaluation of the Time Analysable On-Demand Coherent Cache

The usage of caches in multi- and many-core systems for timing critical applications is a challenging issue. Time-predictability shaped up as the essential characteristic of a cache when talking about the suitability for hard real-time systems. Common cache coherence mechanisms corrupt the timing analysability of a cache memory because of unpredictable interferences between the caches. Thus, these mechanisms are unsuitable for hard real-time systems. In this work, we briefly describe the ODC² together with an extension which increases the cache hit rate. We evaluated the performance of the extended ODC² by comparing it to analysable uncached accesses to shared data and to the well-known but unpredictable MESI and MOESI coherence techniques.