Add C++ multi thread load test

.github/workflows/build.yml

@@ -59,6 +59,7 @@ jobs:
           fi
           ./searchKnnCloserFirst_test
           ./searchKnnWithFilter_test
+          ./multiThreadLoad_test
           ./test_updates
           ./test_updates update
         shell: bash

CMakeLists.txt

@@ -25,6 +25,9 @@ if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
     add_executable(searchKnnWithFilter_test examples/searchKnnWithFilter_test.cpp)
     target_link_libraries(searchKnnWithFilter_test hnswlib)
 
+    add_executable(multiThreadLoad_test examples/multiThreadLoad_test.cpp)
+    target_link_libraries(multiThreadLoad_test hnswlib)
+
     add_executable(main main.cpp sift_1b.cpp)
     target_link_libraries(main hnswlib)
 endif()

examples/multiThreadLoad_test.cpp

@@ -0,0 +1,53 @@
+#include "../hnswlib/hnswlib.h"
+#include <thread>
+
+int main() {
+    int d = 16;
+    int max_elements = 100;
+
+    std::mt19937 rng;
+    rng.seed(47);
+    std::uniform_real_distribution<> distrib_real;
+
+    hnswlib::L2Space space(d);
+    hnswlib::HierarchicalNSW<float>* alg_hnsw = new hnswlib::HierarchicalNSW<float>(&space, max_elements);
+
+    int num_threads = 40;
+    int num_ids = 1;
+
+    int num_iterations = 10;
+    int start_id = 0;
+
+    while (true) {
+        std::uniform_int_distribution<> distrib_int(start_id, start_id + num_ids - 1);
+        std::vector<std::thread> threads;
+        for (size_t thread_id = 0; thread_id < num_threads; thread_id++) {
+            threads.push_back(
+                std::thread(
+                    [&] {
+                        for (int iter = 0; iter < num_iterations; iter++) {
+                            std::vector<float> data(d);
+                            int id = distrib_int(rng);
+                            //std::cout << id << std::endl;
+                            for (int i = 0; i < d; i++) {
+                                data[i] = distrib_real(rng);
+                            }
+                            alg_hnsw->addPoint(data.data(), id);
+                        }
+                    }
+                )
+            );
+        }
+        for (auto &thread : threads) {
+            thread.join();
+        }
+        //std::cout << alg_hnsw->cur_element_count << std::endl;
+        if (alg_hnsw->cur_element_count > max_elements - num_ids) {
+            //std::cout << "Exit" << std::endl;
+            break;
+        }
+        start_id += num_ids;
+    }
+
+    return 0;
+}