Method MergeToRootScope

paddle/fluid/framework/multi_trainer.cc:198–210

template <typename T>
void MultiTrainer::MergeToRootScope(phi::DenseTensor* root_tensor,
                                    phi::DenseTensor* tensor) {
  DenseTensor tmp_root;
  TensorCopy(*root_tensor, CPUPlace(), &tmp_root);
  T* tmp_root_data = tmp_root.data<T>();
  DenseTensor tmp_tensor;
  TensorCopy(*tensor, CPUPlace(), &tmp_tensor);
  T* data = tmp_tensor.data<T>();
  for (int i = 0; i < tmp_tensor.numel(); i++) {
    tmp_root_data[i] += data[i];
  }
  TensorCopy(tmp_root, CPUPlace(), root_tensor);
}
void MultiTrainer::MergeWorkerVars() {
  for (size_t i = 0; i < need_merge_var_names_.size(); i++) {
    Variable* root_var = root_scope_->FindVar(need_merge_var_names_[i]);