ctcyang commented on a change in pull request #11591: [MXNET-331] Single machine All Reduce Topology-aware Communication (Updated) URL: https://github.com/apache/incubator-mxnet/pull/11591#discussion_r204595732
########## File path: src/kvstore/comm_tree.h ########## @@ -0,0 +1,518 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ + +/** + * Copyright (c) 2018 by Contributors + */ +#ifndef MXNET_KVSTORE_COMM_TREE_H_ +#define MXNET_KVSTORE_COMM_TREE_H_ +#include <dmlc/omp.h> +#include <string> +#include <algorithm> +#include <utility> +#include <limits> +#include <vector> +#include <tuple> +#include <thread> +#include <map> +#include "mxnet/ndarray.h" +#include "gradient_compression.h" +#include "../ndarray/ndarray_function.h" +#include "../operator/tensor/sparse_retain-inl.h" +#include "./kvstore_utils.h" +#include "./gpu_topology.h" +namespace mxnet { +namespace kvstore { +/** + * \brief an implementation of Comm that performs reduction on device + * directly using tree. + * + * It is faster if the total device-to-device bandwidths is larger than + * device-to-cpu, which is often true for 4 or 8 GPUs. But it uses more device + * memory. + */ +class CommDeviceTree : public CommDevice { + public: + CommDeviceTree() { + inited_ = false; + gpuarray_bound_ = dmlc::GetEnv("MXNET_KVSTORE_GPUARRAY_BOUND", 10000000); + backtrack_ = dmlc::GetEnv("MXNET_KVSTORE_BACKTRACK", 0); Review comment: Added documentation. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
