round_robin.h

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Distributed under BSD 3-Clause license.                                   *
 * Copyright by The HDF Group.                                               *
 * Copyright by the Illinois Institute of Technology.                        *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of Hermes. The full Hermes copyright notice, including  *
 * terms governing use, modification, and redistribution, is contained in    *
 * the COPYING file, which can be found at the top directory. If you do not  *
 * have access to the file, you may request a copy from help@hdfgroup.org.   *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
#ifndef HERMES_SRC_DPE_ROUND_ROBIN_H_
#define HERMES_SRC_DPE_ROUND_ROBIN_H_
 
#include <map>
 
#include "data_placement_engine.h"
 
namespace hermes {
 
using api::Status;
 
class RoundRobin : public DPE {
 private:
  static inline int current_device_index_{}; 
  static std::vector<DeviceID> devices_;     
  std::mutex device_index_mutex_;            
 public:
  RoundRobin() : DPE(PlacementPolicy::kRoundRobin) {
    device_index_mutex_.lock();
  }
  ~RoundRobin() { device_index_mutex_.unlock(); }
 
  Status Placement(const std::vector<size_t> &blob_sizes,
                   const std::vector<u64> &node_state,
                   const std::vector<TargetID> &targets,
                   const api::Context &ctx,
                   std::vector<PlacementSchema> &output);
 
  size_t GetNumDevices() const;
 
  int GetCurrentDeviceIndex() const;
 
  DeviceID GetDeviceByIndex(int i) const;
 
  void SetCurrentDeviceIndex(int new_device_index);
 
  static void InitDevices(hermes::Config *config,
                          std::shared_ptr<api::Hermes> result);
  static void InitDevices(int count, int start_val = 0);
 
 private:
  Status AddSchema(size_t index, std::vector<u64> &node_state,
                   const std::vector<size_t> &blob_sizes,
                   const std::vector<TargetID> &targets,
                   PlacementSchema &output);
};
 
}  // namespace hermes
 
#endif  // HERMES_SRC_DPE_ROUND_ROBIN_H_