EnergyEfficientRegion.hpp

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#ifndef ENERGYEFFICIENTREGION_HPP_INCLUDE
#define ENERGYEFFICIENTREGION_HPP_INCLUDE

#include <vector>

#include "geopm_time.h"

namespace geopm
{

    class IPlatformIO;

    /// @brief Holds the performance history of a Region.
    class EnergyEfficientRegion
    {
        public:
            EnergyEfficientRegion(IPlatformIO &platform_io, double freq_min,
                                  double freq_max, double freq_step,
                                  int runtime_idx,
                                  int pkg_energy_idx,
                                  int dram_energy_idx);
            virtual ~EnergyEfficientRegion() = default;
            double freq(void) const;
            void update_entry(void);
            void update_exit(void);
        private:
            // Used to determine whether performance degraded or not.
            // Higher is better.
            virtual double perf_metric();
            virtual double energy_metric();

            IPlatformIO &m_platform_io;
            const size_t M_NUM_FREQ;
            size_t m_curr_idx;
            double m_target = 0.0;
            const double M_PERF_MARGIN = 0.10;  // up to 10% degradation allowed
            const double M_ENERGY_MARGIN = 0.025;
            const size_t M_MIN_BASE_SAMPLE = 4;

            std::vector<size_t> m_num_increase;
            const size_t M_MAX_INCREASE = 4;
            bool m_is_learning = true;

            std::vector<double> m_allowed_freq;
            std::vector<double> m_perf_max;
            std::vector<double> m_energy_min;
            std::vector<size_t> m_num_sample;
            double m_start_energy = 0.0;

            int m_runtime_idx;
            int m_pkg_energy_idx;
            int m_dram_energy_idx;
    };

} // namespace geopm

#endif