6.1 Conclusions
Asymmetric multicores processors have been recently proposed a good com-promise between performance and power efficiency. However, they also face new challenges such as scheduling problems and resource utilization prob-lems. Many studies devised new technique to utilize AMPs efficiently. [6, 15, 18, 26]. This thesis presents a fuzzy scheduler based on fuzzy control theory for JVM to migrate Java threads to the proper cores for energy saving on AMPs. In our previous work, the IPC scheduler could not make a right core decision for some of CPU-intensive programs because it did not consider data dependency and that would cause execution time to increase heavily. Our fuzzy scheduler takes RSR and cache miss rate into account such that the fuzzy scheduler could make the right core decision for all benchmark
pro-grams. Our experiments show 25% energy saving and 20% EDP benefit for memory-intensive applications compared to the results at the fastest core. In our experiments, we could not get any benefit for CPU-intensive programs, because they could not execute at a lower frequency efficiently.
6.2 Future works
In the future work, we would like to consider more about OS scheduling issues, such as load balance and asymmetry-aware OS thread assignment.
We would also like to eliminate the constraint of thread number to make more efficient utilization. One of other future directions is to use a wider diversity of asymmetric multicore systems in different cache sizes, or having different number of execution units, or supporting in-order or out-of-order execution and so on.
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