April 21, 2011 -- The memory hierarchy (including caches and main memory) can consume as much as 50% of an embedded system power. This power is very application dependent, and tuning caches for a given application is a good way to reduce power consumption.

However, application programs are complex and include many subroutines, each of them having their own optimal cache configuration. We developed a low power dynamically reconfigurable cache controller and its simulator called Cache Evaluation Software.

This simulator allows user to specify cache reconfigurations within the application program and evaluates time and power consumption for each configuration phase taking into account reconfiguration costs. It allows a fast assessment of optimal cache configuration for subroutines and demonstrates that power consumption of the memory system can be reduced by 83% thanks to this approach. We also used it to simulate our self–configurable cache and proved a power reduction of 70% for the memory system and thus avoiding the difficult task of choosing the configuration parameters of the cache.

By Olivier Montfort. (Monfort is with Dolphin Integration.)