Replace deleted elements at addition

.github/workflows/build.yml

@@ -19,6 +19,7 @@ jobs:
         run: python -m pip install .
 
       - name: Test
+        timeout-minutes: 15
         run: python -m unittest discover -v --start-directory python_bindings/tests --pattern "*_test*.py"
 
   test_cpp:
@@ -52,13 +53,15 @@ jobs:
         shell: bash
 
       - name: Test
+        timeout-minutes: 15
         run: |
           cd build
           if [ "$RUNNER_OS" == "Windows" ]; then
             cp ./Release/* ./
           fi
           ./searchKnnCloserFirst_test
           ./searchKnnWithFilter_test
+          ./multiThreadLoad_test
           ./test_updates
           ./test_updates update
         shell: bash

.gitignore

@@ -9,3 +9,4 @@ var/
 .idea/
 .vscode/
 .vs/
+**.DS_Store

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 +1,140 @@
+#include "../hnswlib/hnswlib.h"
+#include <thread>
+#include <chrono>
+
+
+int main() {
+    std::cout << "Running multithread load test" << std::endl;
+    int d = 16;
+    int max_elements = 1000;
+
+    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, 2 * max_elements);
+
+    std::cout << "Building index" << std::endl;
+    int num_threads = 40;
+    int num_labels = 10;
+
+    int num_iterations = 10;
+    int start_label = 0;
+
+    // run threads that will add elements to the index
+    // about 7 threads (the number depends on num_threads and num_labels)
+    // will add/update element with the same label simultaneously
+    while (true) {
+        // add elements by batches
+        std::uniform_int_distribution<> distrib_int(start_label, start_label + num_labels - 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);
+                            hnswlib::labeltype label = distrib_int(rng);
+                            for (int i = 0; i < d; i++) {
+                                data[i] = distrib_real(rng);
+                            }
+                            alg_hnsw->addPoint(data.data(), label);
+                        }
+                    }
+                )
+            );
+        }
+        for (auto &thread : threads) {
+            thread.join();
+        }
+        if (alg_hnsw->cur_element_count > max_elements - num_labels) {
+            break;
+        }
+        start_label += num_labels;
+    }
+
+    // insert remaining elements if needed
+    for (hnswlib::labeltype label = 0; label < max_elements; label++) {
+        auto search = alg_hnsw->label_lookup_.find(label);
+        if (search == alg_hnsw->label_lookup_.end()) {
+            std::cout << "Adding " << label << std::endl;
+            std::vector<float> data(d);
+            for (int i = 0; i < d; i++) {
+                data[i] = distrib_real(rng);
+            }
+            alg_hnsw->addPoint(data.data(), label);
+        }
+    }
+
+    std::cout << "Index is created" << std::endl;
+
+    bool stop_threads = false;
+    std::vector<std::thread> threads;
+
+    // create threads that will do markDeleted and unmarkDeleted of random elements
+    // each thread works with specific range of labels
+    std::cout << "Starting markDeleted and unmarkDeleted threads" << std::endl;
+    num_threads = 20;
+    int chunk_size = max_elements / num_threads;
+    for (size_t thread_id = 0; thread_id < num_threads; thread_id++) {
+        threads.push_back(
+            std::thread(
+                [&, thread_id] {
+                    std::uniform_int_distribution<> distrib_int(0, chunk_size - 1);
+                    int start_id = thread_id * chunk_size;
+                    std::vector<bool> marked_deleted(chunk_size);
+                    while (!stop_threads) {
+                        int id = distrib_int(rng);
+                        hnswlib::labeltype label = start_id + id;
+                        if (marked_deleted[id]) {
+                            alg_hnsw->unmarkDelete(label);
+                            marked_deleted[id] = false;
+                        } else {
+                            alg_hnsw->markDelete(label);
+                            marked_deleted[id] = true;
+                        }
+                    }
+                }
+            )
+        );
+    }
+
+    // create threads that will add and update random elements
+    std::cout << "Starting add and update elements threads" << std::endl;
+    num_threads = 20;
+    std::uniform_int_distribution<> distrib_int_add(max_elements, 2 * max_elements - 1);
+    for (size_t thread_id = 0; thread_id < num_threads; thread_id++) {
+        threads.push_back(
+            std::thread(
+                [&] {
+                    std::vector<float> data(d);
+                    while (!stop_threads) {
+                        hnswlib::labeltype label = distrib_int_add(rng);
+                        for (int i = 0; i < d; i++) {
+                            data[i] = distrib_real(rng);
+                        }
+                        alg_hnsw->addPoint(data.data(), label);
+                        std::vector<float> data = alg_hnsw->getDataByLabel<float>(label);
+                        float max_val = *max_element(data.begin(), data.end());
+                        // never happens but prevents compiler from deleting unused code
+                        if (max_val > 10) {
+                            throw std::runtime_error("Unexpected value in data");
+                        }
+                    }
+                }
+            )
+        );
+    }
+
+    std::cout << "Sleep and continue operations with index" << std::endl;
+    int sleep_ms = 60 * 1000;
+    std::this_thread::sleep_for(std::chrono::milliseconds(sleep_ms));
+    stop_threads = true;
+    for (auto &thread : threads) {
+        thread.join();
+    }
+
+    std::cout << "Finish" << std::endl;
+    return 0;
+}