text: // 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.
  
  #include "wrapper/KnowhereResource.h"
  #include "knowhere/index/vector_index/helpers/FaissGpuResourceMgr.h"
  #include "server/Config.h"
  
  #include <map>
  #include <set>
  #include <string>
  #include <utility>
  #include <vector>
  
  namespace milvus {
  namespace engine {
  
  constexpr int64_t M_BYTE = 1024 * 1024;
  
  Status
  KnowhereResource::Initialize() {
      struct GpuResourceSetting {
          int64_t pinned_memory = 300 * M_BYTE;
          int64_t temp_memory = 300 * M_BYTE;
          int64_t resource_num = 2;
      };
      using GpuResourcesArray = std::map<int64_t, GpuResourceSetting>;
      GpuResourcesArray gpu_resources;
      Status s;
  
      // get build index gpu resource
      server::Config& config = server::Config::GetInstance();
  
      int32_t build_index_gpu;
      s = config.GetDBConfigBuildIndexGPU(build_index_gpu);
      if (!s.ok())
          return s;
  
      gpu_resources.insert(std::make_pair(build_index_gpu, GpuResourceSetting()));
  
      // get search gpu resource
      std::vector<std::string> pool;
      s = config.GetResourceConfigPool(pool);
      if (!s.ok())
          return s;
  
      std::set<uint64_t> gpu_ids;
      for (auto& resource : pool) {
          if (resource.length() < 4 || resource.substr(0, 3) != "gpu") {
              // invalid
              continue;
          }
          auto gpu_id = std::stoi(resource.substr(3));
          gpu_resources.insert(std::make_pair(gpu_id, GpuResourceSetting()));
      }
  
      // init gpu resources
      for (auto iter = gpu_resources.begin(); iter != gpu_resources.end(); ++iter) {
          knowhere::FaissGpuResourceMgr::GetInstance().InitDevice(iter->first, iter->second.pinned_memory,
                                                                  iter->second.temp_memory, iter->second.resource_num);
      }
  
      return Status::OK();
  }
  
  Status
  KnowhereResource::Finalize() {
      knowhere::FaissGpuResourceMgr::GetInstance().Free();  // free gpu resource.
      return Status::OK();
  }
  
  }  // namespace engine
  }  // namespace milvus
  