Using Multiple Input, Multiple Output Formal Control to Maximize Resource Efficiency in Architectures

Authors: Raghavendra Pradyumna Pothukuchi, Amin Ansari, Petros Voulgaris, and Josep Torellas
Venue:    ISCA 2016

This paper using control theory to design an adaptive system. While many approaches exist, the key novelty to this work is the multiple-input, multiple-output coordination which considers multiple trade-offs simultaneously to tune the system. The framework essentially uses several "training set" workloads to train a controller which is able to predict power and performance. Then, a "test set" of workloads is used to evaluate the controller's performance when trying to tune the power-performance trade-offs. The benefit is formal guarantees, however, the cost is the user requirement to specify reference values. More specifically, rather than "maximize x trade-off", MIMO controller works best by specifying "achieve values x1, x2, with weights w1 and w2" for importance.

Overall, this work excellently integrates considerations such as monitoring frequency, reconfiguration overheads, and variables goals (power vs. performance).

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