Method fixed_sample_rate_run

libCacheSim/mrcProfiler/mrcProfiler.cpp:92–169

}

void mrcProfiler::MRCProfilerSHARDS::fixed_sample_rate_run() {
  // 1. init
  request_t *req = new_request();
  double sample_rate = params_.shards_params.sample_rate;
  std::vector<double> local_hit_cnt_vec(mrc_size_vec.size(), 0);
  std::vector<double> local_hit_size_vec(mrc_size_vec.size(), 0);
  uint64_t sample_max = UINT64_MAX * sample_rate;
  if (sample_rate == 1) {
    INFO("sample_rate is 1, no need to sample\n");
    sample_max = UINT64_MAX;
  }
  double sampled_cnt = 0, sampled_size = 0;
  int64_t current_time = 0;
  robin_hood::unordered_map<obj_id_t, int64_t> last_access_time_map;
  SplayTree<int64_t, uint64_t> rd_tree;

  // 2. go through the trace
  read_one_req(reader_, req);
  /* going through the trace */
  do {
    DEBUG_ASSERT(req->obj_size != 0);
    n_req_ += 1;
    sum_obj_size_req += req->obj_size;

    uint64_t hash_value = get_hash_value_int_64_with_salt(
        req->obj_id, params_.shards_params.salt);
    current_time += 1;
    if (hash_value <= sample_max) {
      sampled_cnt += 1.0 / sample_rate;
      sampled_size += 1.0 * req->obj_size / sample_rate;

      if (last_access_time_map.count(req->obj_id)) {
        int64_t last_access_time = last_access_time_map[req->obj_id];
        size_t stack_distance =
            rd_tree.getDistance(last_access_time) / sample_rate;

        last_access_time_map[req->obj_id] = current_time;

        // update tree
        rd_tree.erase(last_access_time);
        rd_tree.insert(current_time, req->obj_size);

        // find bucket to increase hit cnt and hit size
        auto it = std::lower_bound(mrc_size_vec.begin(), mrc_size_vec.end(),
                                   stack_distance);

        if (it != mrc_size_vec.end()) {
          // update hit cnt and hit size
          int idx = std::distance(mrc_size_vec.begin(), it);
          local_hit_cnt_vec[idx] += 1.0 / sample_rate;
          local_hit_size_vec[idx] += 1.0 * req->obj_size / sample_rate;
        }

      } else {
        last_access_time_map[req->obj_id] = current_time;
        // update the tree
        rd_tree.insert(current_time, req->obj_size);
      }