| /** |
| * Copyright 2016, Quickstep Research Group, Computer Sciences Department, |
| * University of Wisconsin—Madison. |
| * |
| * Licensed 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. |
| **/ |
| |
| #ifndef QUICKSTEP_CLI_DEFAULTS_CONFIGURATOR_HPP_ |
| #define QUICKSTEP_CLI_DEFAULTS_CONFIGURATOR_HPP_ |
| |
| #include <thread> // NOLINT(build/c++11) |
| #include <unordered_map> |
| #include <vector> |
| |
| #include "utility/Macros.hpp" |
| |
| #ifdef QUICKSTEP_HAVE_LIBNUMA |
| #include <numa.h> |
| #endif |
| |
| namespace quickstep { |
| |
| /** \addtogroup CLI |
| * @{ |
| **/ |
| |
| /** |
| * @brief A static class for setting the default configuration parameters in |
| * Quickstep. |
| **/ |
| class DefaultsConfigurator { |
| public: |
| /** |
| * @brief Get the number of concurrent threads supported by the hardware, |
| * |
| * @note This function will return 0, if it fails (which it may on some |
| * machines/environments). |
| **/ |
| static std::size_t GetNumHardwareThreads() { |
| return std::thread::hardware_concurrency(); |
| } |
| |
| /** |
| * @brief Get the number of NUMA nodes covered by the given worker affinities |
| * to the CPU cores. |
| * |
| * @param worker_cpu_affinities A vector V where V[i] is the CPU core to which |
| * worker with index i is affinitized. |
| * |
| * @return The number of NUMA nodes that are covered by the given set of |
| * workers. |
| **/ |
| static std::size_t GetNumNUMANodesCoveredByWorkers(const std::vector<int> &worker_cpu_affinities) { |
| if (!worker_cpu_affinities.empty()) { |
| #ifdef QUICKSTEP_HAVE_LIBNUMA |
| // Key = NUMA node, value = whether there is at least one worker whose |
| // affinity is set to a core on the given NUMA node. |
| std::unordered_map<int, bool> any_worker_on_numa_node; |
| for (const int curr_cpu_core_id : worker_cpu_affinities) { |
| const int curr_numa_node_id = numa_node_of_cpu(curr_cpu_core_id); |
| if (curr_numa_node_id >= 0) { |
| // Note - For the purpose of this function, the value is always true. |
| // Therefore, we can rely on the size of the map to get the count. |
| any_worker_on_numa_node[curr_numa_node_id] = true; |
| } |
| } |
| return any_worker_on_numa_node.size(); |
| #endif |
| } |
| // When libnuma is not available, or worker affinities are not specified, |
| // the default return value is 1. |
| return 1; |
| } |
| |
| private: |
| /** |
| * @brief Private constructor to disable instantiation of the class. |
| **/ |
| DefaultsConfigurator(); |
| |
| DISALLOW_COPY_AND_ASSIGN(DefaultsConfigurator); |
| }; |
| /** @} */ |
| |
| } // namespace quickstep |
| |
| #endif // QUICKSTEP_CLI_DEFAULTS_CONFIGURATOR_HPP_ |
| |