milvus/core/src/scheduler/Algorithm.cpp
Jin Hai e1027e9e65
#1240 Update license declaration of each file (#1241)
* #1240 Update license declaration of each files

Signed-off-by: jinhai <hai.jin@zilliz.com>

* #1240 Update CHANGELOG

Signed-off-by: jinhai <hai.jin@zilliz.com>
2020-02-17 23:40:58 +08:00

100 lines
3.5 KiB
C++

// Copyright (C) 2019-2020 Zilliz. All rights reserved.
//
// 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.
#include "scheduler/Algorithm.h"
#include <limits>
#include <unordered_map>
#include <utility>
namespace milvus {
namespace scheduler {
constexpr uint64_t MAXINT = std::numeric_limits<uint32_t>::max();
uint64_t
ShortestPath(const ResourcePtr& src, const ResourcePtr& dest, const ResourceMgrPtr& res_mgr,
std::vector<std::string>& path) {
uint64_t num_of_resources = res_mgr->GetAllResources().size();
std::unordered_map<uint64_t, std::string> id_name_map;
std::unordered_map<std::string, uint64_t> name_id_map;
for (uint64_t i = 0; i < num_of_resources; ++i) {
id_name_map.insert(std::make_pair(i, res_mgr->GetAllResources().at(i)->name()));
name_id_map.insert(std::make_pair(res_mgr->GetAllResources().at(i)->name(), i));
}
std::vector<std::vector<uint64_t>> dis_matrix;
dis_matrix.resize(num_of_resources);
for (uint64_t i = 0; i < num_of_resources; ++i) {
dis_matrix[i].resize(num_of_resources);
for (uint64_t j = 0; j < num_of_resources; ++j) {
dis_matrix[i][j] = MAXINT;
}
dis_matrix[i][i] = 0;
}
std::vector<bool> vis(num_of_resources, false);
std::vector<uint64_t> dis(num_of_resources, MAXINT);
for (auto& res : res_mgr->GetAllResources()) {
auto cur_node = std::static_pointer_cast<Node>(res);
auto cur_neighbours = cur_node->GetNeighbours();
for (auto& neighbour : cur_neighbours) {
auto neighbour_res = std::static_pointer_cast<Resource>(neighbour.neighbour_node);
dis_matrix[name_id_map.at(res->name())][name_id_map.at(neighbour_res->name())] =
neighbour.connection.transport_cost();
}
}
for (uint64_t i = 0; i < num_of_resources; ++i) {
dis[i] = dis_matrix[name_id_map.at(src->name())][i];
}
vis[name_id_map.at(src->name())] = true;
std::vector<int64_t> parent(num_of_resources, -1);
for (uint64_t i = 0; i < num_of_resources; ++i) {
uint64_t minn = MAXINT;
uint64_t temp = 0;
for (uint64_t j = 0; j < num_of_resources; ++j) {
if (!vis[j] && dis[j] < minn) {
minn = dis[j];
temp = j;
}
}
vis[temp] = true;
if (i == 0) {
parent[temp] = name_id_map.at(src->name());
}
for (uint64_t j = 0; j < num_of_resources; ++j) {
if (!vis[j] && dis_matrix[temp][j] != MAXINT && dis_matrix[temp][j] + dis[temp] < dis[j]) {
dis[j] = dis_matrix[temp][j] + dis[temp];
parent[j] = temp;
}
}
}
int64_t parent_idx = parent[name_id_map.at(dest->name())];
if (parent_idx != -1) {
path.push_back(dest->name());
}
while (parent_idx != -1) {
path.push_back(id_name_map.at(parent_idx));
parent_idx = parent[parent_idx];
}
return dis[name_id_map.at(dest->name())];
}
} // namespace scheduler
} // namespace milvus