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Examples

This section uses the sift-128-euclidean.hdf5 dataset with 80 threads as an example. Run the following command to obtain the dataset:

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wget http://ann-benchmarks.com/sift-128-euclidean.hdf5 --no-check-certificate

Assume that the directory where the program runs is /path/to/kbest_test. The complete directory structure is as follows:

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├── build                                                   // Store build files, which are automatically generated when build.sh is executed.
├── build.sh                                                // Run build.sh to build an executable file named run.
├── CMakeLists.txt                        
├── datasets                                                // Store the dataset.
      └── sift-128-euclidean.hdf5
├── graph_indices                                           // Store the built graph index, which needs to be manually created.
      └── sift-128-euclidean_KGN-RNN_R_50_L_100.kgn         // The built graph index is generated when the executable file run is executed. (In the corresponding dataset configuration file, index_save_or_load is set to save and save_types is set to save_graph.)
├── searcher_indices                                        // Store the built searcher, which needs to be manually created.
      └── sift.ksn         // The built searcher is generated when the executable file run is executed. (In the corresponding dataset configuration file, index_save_or_load is set to save and save_types is set to save_searcher.)
├── main.cpp                                                // The file that contains the running functions.
├── run                                                     // The executable file, which is generated after build.sh is executed.
└── sift.config                                             // The corresponding dataset configuration file.

Procedure:

  1. Assume that the program runs in the /path/to/kbest_test directory. Check whether the build.sh, CMakeLists.txt, datasets/sift-128-euclidean.hdf5, main.cpp and sift.config files exist in the directory. build.sh, CMakeLists.txt, main.cpp, and sift.config are provided at the end of this section.
  2. Ensure that the num_numa_nodes in the sift.config file is set to the actual number of NUMA nodes during run time.
  3. If the command is executed for the first time, ensure that index_save_or_load in the sift.config file is set to save. In subsequent execution, the value can be changed to load to use the built graph index or searcher for query.
  4. Install the hdf5-devel dependency.
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    yum install hdf5-devel openssl-devel libcurl-devel
    
  5. Run build.sh.
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    sh build.sh
    
  6. Run the executable file run.
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    ./run 80 2 -1 sift.config
    

    The test command parameters are described as follows:

    ./run <threads> <qurey_mode> <batch_size> <config_name>
    • threads indicates the number of running threads.
    • qurey_mode indicates the test mode. 1 indicates the batch query mode, that is, batch_size queries are executed at a time. 2 indicates the concurrent single query mode, that is, each thread executes a single query concurrently. In this case, batch_size is invalid.
    • batch_size indicates the number of queries to be executed at a time in batch query mode. If batch_size is set to -1, all queries in the dataset are executed at a time.
    • config_name indicates the name of the configuration file corresponding to the test dataset.

    The command output is as follows:

The content of build.sh is as follows:
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mkdir build
cd build
cmake .. -DCMAKE_INCLUDE_PATH=/usr/local/sra_recall/include -DCMAKE_LIBRARY_PATH=/usr/local/sra_recall/lib
make -j
cp run ..
The content of CMakeLists.txt is as follows:
EXECUTE_PROCESS(COMMAND uname -m COMMAND tr -d '\n' OUTPUT_VARIABLE ARCHITECTURE)
message(STATUS "Architecture: ${ARCHITECTURE}")

if(${ARCHITECTURE} STREQUAL "aarch64")
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -ldl -lz -gdwarf-2")
    include_directories(/usr/include/hdf5)
else()
    set(CMAKE_C_COMPILER gcc)
    set(CMAKE_CXX_COMPILER g++)
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -lhdf5")
endif()

cmake_minimum_required(VERSION 3.12.0)
project(best LANGUAGES C CXX)
set(CMAKE_CXX_STANDARD 20)

message(PROJECT_SOURCE_DIR="${PROJECT_SOURCE_DIR}")

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++2a -falign-jumps=64 -fopenmp -fPIC -Ofast -march=armv8.2-a+dotprod")
set(KBEST_INCLUDE_DIRS "/usr/local/sra_recall/include")

find_package(HDF5 REQUIRED COMPONENTS C HL)
include_directories(${HDF5_INCLUDE_DIRS})
include_directories(${KBEST_INCLUDE_DIRS})

message(HDF5_INCLUDE_DIRS="${HDF5_INCLUDE_DIRS}")
message(HDF5_LIBRARIES="${HDF5_LIBRARIES}")

set(KBEST_SHARED_LIB_PATH "/usr/local/sra_recall/lib")
message(KBEST_SHARED_LIB_PATH="${KBEST_SHARED_LIB_PATH}")
link_directories(${KBEST_SHARED_LIB_PATH})

add_executable(run main.cpp)

if(${ARCHITECTURE} STREQUAL "aarch64")
    target_link_libraries(run ${KBEST_SHARED_LIB_PATH}/libkbest.so ${HDF5_LIBRARIES} -lcrypto -lcurl -lpthread -lz -ldl -lm -lnuma)
else()
    target_link_libraries(run ${KBEST_SHARED_LIB_PATH}/libkbest.so ${HDF5_LIBRARIES} dl z)
endif()
The content of main.cpp is as follows:
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#include <bits/stdc++.h>
#if defined(__aarch64__)
#include "hdf5.h"
#else
#include <hdf5.h>
#endif
#include "kbest.h"
#include <numa.h>
#include <array>
#include <filesystem>
#include <fstream>
#include <iostream>
#include <memory>
#include <stdexcept>
#include <string>
#include <vector>
using namespace std;

static const char* HDF5_DATASET_TRAIN = "train";
static const char* HDF5_DATASET_TEST = "test";
static const char* HDF5_DATASET_NEIGHBORS = "neighbors";
static const char* HDF5_DATASET_DISTANCES = "distances";

extern bool NUMA_ENABLED;
extern int num_numa_nodes;

void* hdf5_read(const std::string& file_name, const std::string& dataset_name, H5T_class_t dataset_class,
                int32_t& d_out, int32_t& n_out);

double distance(const float* x, const float* y, int d, const std::string metric) {                                      // Calculate the distance.
    if (metric == "L2") {
        double sum = 0.0f;
        for (int i = 0; i < d; ++i) {
            sum += (double)(x[i] - y[i]) * (x[i] - y[i]);
        }
        return sum;
    } else if (metric == "IP") {
        double sum = 0.0f;
        for (int i = 0; i < d; ++i) {
            sum -= (double)x[i] * y[i];
        }
        return sum;
    } else {
        assert(false);
    }
    return 0;
}

int intersect(int64_t* a1, int64_t* a2, int l1, int l2, int index) {                                                    // Calculate the intersection.
    int res = 0;
    for (int i = 0; i < l1; i++) {
        if (a1[i] < 0) { continue; }
        for (int j = 0; j < i; j++) {
            if (a1[i] == a1[j]) { continue; }
        }
        for (int j = 0; j < l2; j++) {
            if (a1[i] == a2[j]) {
                res++;
                break;
            }
        }
    }
    return res;
}

void loadHDF(const std::string& ann_file_name, int32_t& nb, int32_t& nq, int32_t& dim, int32_t& gt_closest,             // Load the dataset.
             float*& data, float*& queries, int64_t*& gt_ids, int consecutiveLog, int& numAllocParts) {
    float* data_one = (float*)hdf5_read(ann_file_name, HDF5_DATASET_TRAIN, H5T_FLOAT, dim, nb);
    queries = (float*)hdf5_read(ann_file_name, HDF5_DATASET_TEST, H5T_FLOAT, dim, nq);
    int32_t* gt_ids_short = (int32_t*)hdf5_read(ann_file_name, HDF5_DATASET_NEIGHBORS, H5T_INTEGER, gt_closest, nq);
    gt_ids = new int64_t[gt_closest * nq];
    for (int i = 0; i < gt_closest * nq; i++) {
        gt_ids[i] = gt_ids_short[i];
    }

    data = data_one;
    numAllocParts = 1;
    delete[] gt_ids_short;
}

static void normalize(float* data, int length) {                                                                        // Normalization.
    double norm = 0;
    for (int i = 0; i < length; i++) {
        norm += data[i] * data[i];
    }
    norm = sqrt(norm);
    if (norm != 0.0f) {
        for (int i = 0; i < length; i++) {
            data[i] /= norm;
            assert(!isnan(data[i]));
        }
    }
}

struct Config {
    int iter_num;
    int topK;
    std::string index_save_or_load;
    std::string save_types;
    std::string index_path;
    std::string searcher_path;
    std::string dataset_path;
    std::string dataset_type;
    std::string metric;
    int L;
    int R;
    int A;
    std::string index_type;
    bool optimize;
    bool batch;
    int kmeans_ep;
    int kmeans_type;
    std::vector<int> level;
    std::vector<int> efs;
    bool numa_enabled;
    int num_numa_nodes;
};

std::vector<int> parse_list(const std::string& str) {
    std::vector<int> result;
    std::stringstream ss(str);
    std::string item;
    while (std::getline(ss, item, ',')) {
        result.push_back(std::stoi(item));
    }
    return result;
}

Config read_config(const std::string& file_path) {
    std::ifstream file(file_path);
    if (!file.is_open()) { std::cout << "[ERROR] config file not found" << std::endl; }

    Config config;
    std::unordered_map<std::string, std::string> config_map;
    std::string line;
    while (std::getline(file, line)) {
        std::istringstream is_line(line);
        std::string key;
        if (std::getline(is_line, key, '=')) {
            std::string value;
            if (std::getline(is_line, value)) { config_map[key] = value; }
        }
    }

    config.iter_num = std::stoi(config_map["iter_num"]);
    std::cout << "iter_num: " << config.iter_num << std::endl;
    config.topK = std::stoi(config_map["topK"]);
    std::cout << "topK: " << config.topK << std::endl;
    config.index_save_or_load = config_map["index_save_or_load"];
    config.save_types = config_map["save_types"];
    config.index_path = config_map["index_path"];
    config.searcher_path = config_map["searcher_path"];
    config.dataset_path = config_map["dataset_path"];
    config.dataset_type = config_map["dataset_type"];
    config.metric = config_map["metric"];
    config.L = std::stoi(config_map["L"]);
    config.R = std::stoi(config_map["R"]);
    config.A = std::stoi(config_map["A"]);
    std::cout << "L: " << config.L << std::endl;
    std::cout << "R: " << config.R << std::endl;
    std::cout << "A: " << config.A << std::endl;
    config.index_type = config_map["index_type"];
    config.optimize = config_map["optimize"] == "true";
    config.batch = config_map["batch"] == "true";
    config.level = parse_list(config_map["level"]);
    config.efs = parse_list(config_map["efs"]);
    config.numa_enabled = config_map["numa_enabled"] == "true";
    config.num_numa_nodes = std::stoi(config_map["num_numa_nodes"]);

    std::cout << std::endl;
    std::cout << "topK: " << config.topK << std::endl;
    std::cout << "index_save_or_load: " << config.index_save_or_load << std::endl;
    std::cout << "save_types: " << config.save_types << std::endl;
    std::cout << "index_path: " << config.index_path << std::endl;
    std::cout << "searcher_path: " << config.searcher_path << std::endl;
    std::cout << "dataset_path: " << config.dataset_path << std::endl;
    std::cout << "dataset_type: " << config.dataset_type << std::endl;
    std::cout << "metric: " << config.metric << std::endl;
    std::cout << "index_type: " << config.index_type << std::endl;
    std::cout << "optimize: " << config_map["optimize"] << std::endl;
    std::cout << "batch: " << config_map["batch"] << std::endl;
    std::cout << "level: " << config_map["level"] << std::endl;
    std::cout << "efs: " << config_map["efs"] << std::endl;
    std::cout << "numa_enabled: " << config_map["numa_enabled"] << std::endl;
    std::cout << "num_numa_nodes: " << config_map["num_numa_nodes"] << std::endl;
    std::cout << std::endl;

    return config;
}

bool checkFileExist(const char* path) {
    std::ifstream file(path);
    if (!file.is_open()) {
        std::cout << "[ERROR] file: " << std::string(path) << " not found" << std::endl;
        return false;
    }
    file.close();
    return true;
}

std::unique_ptr<KBest> best = nullptr;

pthread_mutex_t mtx;
pthread_cond_t cond;
int ready = 0;  

struct KBestSearchParams {
    int n;
    const float* x;
    int k;
    float* distance;
    int64_t* labels;
    int dim;
};

void* ThreadSearch(void* arg) {
    KBestSearchParams* params = static_cast<KBestSearchParams*>(arg);
    pthread_mutex_lock(&mtx);
    while (ready == 0) {  
        pthread_cond_wait(&cond, &mtx);
    }
    pthread_mutex_unlock(&mtx);
    for (int i=0;i<params->n;i++) {
    best->Search(1, params->x+ i*params->dim , params->k, params->distance+i*params->k, params->labels+i*params->k, 1);
    }
    return nullptr;
}

int main(int argc, char** argv) {
    if (argc < 3) {
        cerr << "Usage: " << argv[0] << " <thread_num> <query_batch_size> <config_path>\n";
        exit(1);
    }

    int num_thread_for_use = stoi(argv[1]);
    int query_mode = stoi(argv[2]);
    int query_batch_size = stoi(argv[3]);
    std::string configFile = argv[4];

    if (query_mode != 1 && query_mode != 2) {
        std::cout << "[ERROR] Currently we only support query_mode [1,2], input query_mode: " << query_mode << "\n";
        return -1;
    }

    std::ifstream file(configFile);
    if (!file.is_open()) {
        std::cout << "[ERROR] config file not found" << std::endl;
        return -1;
    }

    Config config = read_config(configFile);

    const int consecutiveLog = 20;
    int numAllocParts = 0;
    float* xb_;
    float* xq_;
    int64_t* gt_ids_;
    int32_t nb_, nq_, dim_, gt_closest;
    printf("start: \n");
    if (!checkFileExist(config.dataset_path.c_str())) { return -1; }                                                    // Read the dataset. The test case uses the HDF5 format.
    if (config.dataset_type == "hdf5") {
        loadHDF(config.dataset_path, nb_, nq_, dim_, gt_closest, xb_, xq_, gt_ids_, consecutiveLog, numAllocParts);
    } else {
        cerr << "error, not recognized dataset type: " << config.dataset_type << ", possible are numpy and hdf5.\n";
        exit(1);
    }

    if (config.metric == "IP") {                                                                                        // Determine the dataset measurement mode. L2 is used in the test case.
        for (int i = 0; i < nb_; i++) {
            normalize(xb_ + i * dim_, dim_);
        }
        for (int i = 0; i < nq_; i++) {
            normalize(xq_ + i * dim_, dim_);
        }
    } else if (config.metric != "L2") {
        cerr << "error, not recognized metric: " << config.metric << ", possible are L2 and IP.\n";
        exit(1);
    }
    printf("After loading data: \n");

    int R = 50;
    int numIters = config.iter_num;
    int closestNum = config.topK;

    NUMA_ENABLED = config.numa_enabled;
    num_numa_nodes = config.num_numa_nodes;

    uint8_t *dataPtr = nullptr;
    size_t dataLength = 0;

    if (config.index_save_or_load == "save") {
        for (auto level : config.level) {
            NUMA_ENABLED = false;
            for (int i = 0; i < 1; i++) {
                auto best_build = std::make_unique<KBest>(dim_, config.R, config.L, config.A, config.metric.c_str(), config.index_type);
                std::cout << "index building ..." << std::endl;
                int saveResult = best_build->Add(nb_, xb_, consecutiveLog, level);                                      // Build a graph index.
                if (config.save_types == "save_searcher") {
                    printf("Searcher is Saving. \n");
                    saveResult = best_build->BuildSearcher();                                                           // Build a searcher.
                    saveResult = best_build->Save(config.searcher_path.c_str());                                        // Save the searcher.
                }
                else if (config.save_types == "save_graph"){
                    //save graph
                    printf("Graph is Saving. \n");
                    saveResult = best_build->SaveGraph(config.index_path.c_str());                                      // Save the graph index.
                }
                else {
                    printf("Index serialize. \n");
                    saveResult = best_build->BuildSearcher();  
                    saveResult = best_build->Serialize(dataPtr, dataLength);                                            // Serialization.
                }

                if (saveResult == -1) {
                return -1;
            }
            }
            NUMA_ENABLED = config.numa_enabled;

        }
    }

    for (auto level : config.level) {
        std::cout << std::endl;

        best = std::make_unique<KBest>(dim_, config.R, config.L, config.A, config.metric.c_str(), config.index_type);

        uint64_t timeTaken = 0;
        chrono::_V2::steady_clock::time_point startTime, endTime;
        startTime = chrono::steady_clock::now();

        int loadResult = 0;

        if (config.save_types == "save_searcher") {
            int loadResult = best->Load(config.searcher_path.c_str());                                                  // Load the searcher.
        }
        else if (config.save_types == "save_graph") {
            int loadResult = best->LoadGraph(config.index_path.c_str());                                                // Load the graph index.
        }
        else {
            int loadResult = best->Deserialize(dataPtr, dataLength);                                                    // Deserialization.
        }
        if (loadResult == -1){
            return -1;
        }

        endTime = chrono::steady_clock::now();
        timeTaken = chrono::duration_cast<chrono::nanoseconds>(endTime - startTime).count();
        std::cout << "index built or read, time: " << (double)timeTaken / 1000 / 1000 / 1000 << "s\n";

        printf("After loading searcher: \n");

        float* distances = new float[nq_ * closestNum]();
        int64_t* labels = new int64_t[nq_ * closestNum]();

        int32_t num_batch = (query_batch_size == -1 ? 1 : (nq_ + query_batch_size - 1) / query_batch_size);

        int32_t base_num_queries = nq_ / num_thread_for_use;
        int32_t left = nq_ % num_thread_for_use;
        std::vector<int> thread_offset(num_thread_for_use + 1, 0);
        for (int i = 0; i < num_thread_for_use; ++i) {
            if (i < left) {
                thread_offset[i + 1] = base_num_queries + 1;
            } else {
                thread_offset[i + 1] = base_num_queries;
            }
        }

        for (int i = 0; i < num_thread_for_use; ++i) {
            thread_offset[i + 1] += thread_offset[i];
        }

        printf("start search: \n");
        for (auto ef : config.efs) {
            best->SetEf(ef);                                                                                            // Set the size of the candidate node list during search.
            double totalTime = 0;
            vector<double> Times;
            double all_qps = 0.0;

            int used_numIters = numIters + 1;

            for (int iter = 0; iter < used_numIters; iter++) {
                std::vector<uint64_t> query_batch_time;
                if (query_mode == 1) {
                    if (query_batch_size == -1) {
                        startTime = chrono::steady_clock::now();
                        best->Search(nq_, xq_, closestNum, distances, labels, num_thread_for_use);                      // Search.
                        endTime = chrono::steady_clock::now();
                        timeTaken = chrono::duration_cast<chrono::nanoseconds>(endTime - startTime).count();
                        query_batch_time.push_back(timeTaken);
                    } else {
                        int32_t st = 0, en = 0, this_batch_size = 0;
                        for (int batch_id = 0; batch_id < num_batch; batch_id++) {
                            st = batch_id * query_batch_size;
                            en = std::min(st + query_batch_size, nq_);
                            this_batch_size = en - st;
                            startTime = chrono::steady_clock::now();
                            best->Search(this_batch_size, xq_ + st * dim_, closestNum, distances + st * closestNum,
                                         labels + st * closestNum, num_thread_for_use);
                            endTime = chrono::steady_clock::now();
                            timeTaken = chrono::duration_cast<chrono::nanoseconds>(endTime - startTime).count();
                            query_batch_time.push_back(timeTaken);
                        }
                    }
                } else {
                    pthread_mutex_init(&mtx, NULL);
                    pthread_cond_init(&cond, NULL);
                    ready = false;
                    std::vector<pthread_t> threads(num_thread_for_use);
                    std::vector<KBestSearchParams> params(num_thread_for_use);
                    for (int i = 0; i < num_thread_for_use; ++i) {
                        params[i].n = nq_;
                        params[i].x = xq_;
                        params[i].k = closestNum;
                        params[i].dim = dim_;
                        params[i].distance = distances;
                        params[i].labels = labels;
                        pthread_create(&threads[i], nullptr, ThreadSearch, &params[i]);
                    }
                    sleep(2);
                    pthread_mutex_lock(&mtx);

                    ready = 1;  
                    pthread_cond_broadcast(&cond);  
                    startTime = chrono::steady_clock::now();
                    pthread_mutex_unlock(&mtx);

                    for (int i = 0; i < num_thread_for_use; i++) {
                        pthread_join(threads[i], NULL);
                    }
                    endTime = chrono::steady_clock::now();
                    timeTaken = chrono::duration_cast<chrono::nanoseconds>(endTime - startTime).count();

                    pthread_mutex_destroy(&mtx);
                    pthread_cond_destroy(&cond);
                    query_batch_time.push_back(timeTaken);
                }
                uint64_t single_iter_time = 0;
                for (auto bt : query_batch_time) {
                    single_iter_time += bt;
                }
                double timeSeconds = (double)single_iter_time / 1000 / 1000 / 1000;

                if (iter != 0) {
                    totalTime += timeSeconds;
                    std::cout << "  runs [" << iter << "/" << numIters << "], qps: " << (double)nq_ / timeSeconds
                              << std::endl;
                    all_qps += (double)nq_ / timeSeconds;
                }
            }
            int found = 0;
            int gtWanted = 10;
            for (int i = 0; i < nq_; i++) {
                found += intersect(gt_ids_ + gt_closest * i, labels + closestNum * i, gtWanted, closestNum, i);
            }

            double avgTime = totalTime / (double)numIters;
            double qps = (double)nq_ / avgTime;                                                                         // Calculate the query per second (QPS).
            double recall = (double)found / nq_ / gtWanted;                                                             // Calculate the recall rate.

            std::cout << "level: " << level << " candListSize: " << ef << std::endl;
            std::cout << "recall: " << recall << " qps: " << all_qps / numIters << std::endl;
        }
        printf("finished: \n");

        delete[] distances;
        delete[] labels;
    }

    delete[] xq_;
    delete[] xb_;
    delete[] gt_ids_;
    return 0;
}

void* hdf5_read(const std::string& file_name, const std::string& dataset_name, H5T_class_t dataset_class,
                int32_t& d_out, int32_t& n_out) {
    hid_t file, dataset, datatype, dataspace, memspace;
    H5T_class_t t_class;
    hsize_t dimsm[3];
    hsize_t dims_out[2];
    hsize_t count[2];
    hsize_t offset[2];
    hsize_t count_out[3];
    hsize_t offset_out[3];
    void* data_out = nullptr;

    file = H5Fopen(file_name.c_str(), H5F_ACC_RDONLY, H5P_DEFAULT);
    dataset = H5Dopen2(file, dataset_name.c_str(), H5P_DEFAULT);
    datatype = H5Dget_type(dataset);
    t_class = H5Tget_class(datatype);
    dataspace = H5Dget_space(dataset);
    H5Sget_simple_extent_dims(dataspace, dims_out, nullptr);

    n_out = dims_out[0];
    d_out = dims_out[1];
    offset[0] = offset[1] = 0;
    count[0] = dims_out[0];
    count[1] = dims_out[1];
    H5Sselect_hyperslab(dataspace, H5S_SELECT_SET, offset, nullptr, count, nullptr);

    dimsm[0] = dims_out[0];
    dimsm[1] = dims_out[1];
    dimsm[2] = 1;
    memspace = H5Screate_simple(3, dimsm, nullptr);

    offset_out[0] = offset_out[1] = offset_out[2] = 0;
    count_out[0] = dims_out[0];
    count_out[1] = dims_out[1];
    count_out[2] = 1;
    H5Sselect_hyperslab(memspace, H5S_SELECT_SET, offset_out, nullptr, count_out, nullptr);

    switch (t_class) {
        case H5T_INTEGER:
            data_out = new int32_t[dims_out[0] * dims_out[1]];
            H5Dread(dataset, H5T_NATIVE_INT32, memspace, dataspace, H5P_DEFAULT, data_out);

            break;
        case H5T_FLOAT:
            data_out = new float[dims_out[0] * dims_out[1]];
            H5Dread(dataset, H5T_NATIVE_FLOAT, memspace, dataspace, H5P_DEFAULT, data_out);
            break;
        default:
            printf("Illegal dataset class type\n");
            break;
    }

    H5Tclose(datatype);
    H5Dclose(dataset);
    H5Sclose(dataspace);
    H5Sclose(memspace);
    H5Fclose(file);

    return data_out;
}
The content of sift.config is as follows:
iter_num=10
topK=10
L=100
R=50
A=60
index_save_or_load=save
index_path=./graph_indices/sift-128-euclidean_KGN-RNN_R_50_L_100.kgn
searcher_path=./searcher_indices/sift-128-euclidean_KGN-RNN_R_50_L_100.ksn
dataset_path=./datasets/sift-128-euclidean.hdf5
dataset_type=hdf5
metric=L2
index_type=RNNDescent
optimize=true
batch=true
numa_enabled=false
num_numa_nodes=4
level=2
efs=72
save_types=save_graph