Evolutionary system for prediction and optimization of hardware architecture performance

The design of computer architectures is a very complex problem. The multiple parameters make the number of possible combinations extremely high. Many researchers have used simulation, although it is a slow solution since evaluating a single point of the search space can take hours. In this work we propose using evolutionary multilayer perceptron (MLP) to compute the performance of an architecture parameter settings. Instead of exploring the search space, simulating many configurations, our method randomly selects some architecture configurations; those are simulated to obtain their performance, and then an artificial neural network is trained to predict the remaining configurations performance. Results obtained show a high accuracy of the estimations using a simple method to select the configurations we have to simulate to optimize the MLP. In order to explore the search space, we have designed a genetic algorithm that uses the MLP as fitness function to find the niche where the best architecture configurations (those with higher performance) are located. Our models need only a small fraction of the design space, obtaining small errors and reducing required simulation by two orders of magnitude.Peer ReviewedPostprint (published version

A Tutorial in Spatial Sampling and Regression Strategies for Microarchitectural Analysis

We present a new simulation paradigm for microarchitectural design evaluation and optimization. This paradigm counters increasing simulation costs attributed to the exponentially increasing size of design spaces and the need for more thorough, comprehensive studies when evaluating increasingly diverse design options. We present a tutorial for (1) obtaining a more comprehensive understanding of the design space by (2) selectively simulating a modest number of designs from that space and then (3) more effectively leveraging that simulation data using techniques in statistical inference. We survey techniques in spatial sampling to obtain designs for simulation. We also detail the statistical techniques required to derive efficient and robust models, interleaving code segments from scripts performing these analyses. The predictive ability and computational efficiency of these regression models enable new capabilities in microarchitectural design space studies. Collectively, our experiences with this paradigm suggest significant potential for accurate, efficient statistical inference in the microarchitectural domain.