[8.2]Fix incorrect assertion in BM_VecSimBasics::UpdateAtBlockSize benchmark

src/VecSim/algorithms/brute_force/brute_force.h

@@ -80,6 +80,8 @@ class BruteForceIndex : public VecSimIndexAbstract<DataType, DistType> {
         idToLabelMapping.shrink_to_fit();
         resizeLabelLookup(idToLabelMapping.size());
     }
+
+    size_t indexMetaDataCapacity() const override { return idToLabelMapping.capacity(); }
 #endif
 
 protected:

src/VecSim/algorithms/hnsw/hnsw.h

@@ -310,6 +310,8 @@ class HNSWIndex : public VecSimIndexAbstract<DataType, DistType>,
             resizeLabelLookup(idToMetaData.size());
         }
     }
+
+    size_t indexMetaDataCapacity() const override { return idToMetaData.capacity(); }
 #endif
 
 protected:

src/VecSim/algorithms/hnsw/hnsw_tiered.h

@@ -248,6 +248,10 @@ class TieredHNSWIndex : public VecSimTieredIndex<DataType, DistType> {
 
 #ifdef BUILD_TESTS
     void getDataByLabel(labelType label, std::vector<std::vector<DataType>> &vectors_output) const;
+    size_t indexMetaDataCapacity() const override {
+        return this->backendIndex->indexMetaDataCapacity() +
+               this->frontendIndex->indexMetaDataCapacity();
+    }
 #endif
 };
 

src/VecSim/algorithms/svs/svs.h

@@ -705,6 +705,7 @@ class SVSIndex : public VecSimIndexAbstract<svs_details::vecsim_dt<DataType>, fl
 
 public:
     void fitMemory() override {}
+    size_t indexMetaDataCapacity() const override { return this->indexCapacity(); }
     std::vector<std::vector<char>> getStoredVectorDataByLabel(labelType label) const override {
 
         // For compressed/quantized indices, this function is not meaningful

src/VecSim/algorithms/svs/svs_tiered.h

@@ -457,6 +457,12 @@ class TieredSVSIndex : public VecSimTieredIndex<DataType, float> {
     backend_index_t *GetBackendIndex() { return this->backendIndex; }
     void submitSingleJob(AsyncJob *job) { Base::submitSingleJob(job); }
     void submitJobs(vecsim_stl::vector<AsyncJob *> &jobs) { Base::submitJobs(jobs); }
+    size_t indexMetaDataCapacity() const override {
+        std::shared_lock<std::shared_mutex> flat_lock(this->flatIndexGuard);
+        std::shared_lock<std::shared_mutex> main_lock(this->mainIndexGuard);
+        return this->frontendIndex->indexMetaDataCapacity() +
+               this->backendIndex->indexMetaDataCapacity();
+    }
 #endif
 
 private:

src/VecSim/vec_sim_interface.h

@@ -217,5 +217,15 @@ struct VecSimIndexInterface : public VecsimBaseObject {
     }
 #ifdef BUILD_TESTS
     virtual void fitMemory() = 0;
+    /**
+     * @brief get the capacity of the meta data containers.
+     *
+     * @return The capacity of the meta data containers in number of elements.
+     * The value returned from this function may differ from the indexCapacity() function. For
+     * example, in HNSW, the capacity of the meta data containers is the capacity of the labels
+     * lookup table, while the capacity of the data containers is the capacity of the vectors
+     * container.
+     */
+    virtual size_t indexMetaDataCapacity() const = 0;
 #endif
 };

tests/benchmark/bm_vecsim_basics.h

@@ -318,6 +318,9 @@ void BM_VecSimBasics<index_type_t>::UpdateAtBlockSize(benchmark::State &st) {
     // Calculate vectors needed to reach next block boundary
     size_t vecs_to_blocksize =
         BM_VecSimGeneral::block_size - (initial_index_size % BM_VecSimGeneral::block_size);
+    size_t initial_index_cap = index->indexMetaDataCapacity();
+    assert(initial_index_cap == N_VECTORS + vecs_to_blocksize);
+
     assert(vecs_to_blocksize < BM_VecSimGeneral::block_size);
     labelType initial_label_count = index->indexLabelCount();
     labelType curr_label = initial_label_count;
@@ -342,24 +345,29 @@ void BM_VecSimBasics<index_type_t>::UpdateAtBlockSize(benchmark::State &st) {
 
     // Benchmark loop: repeatedly delete/add same vector to trigger grow-shrink cycles
     labelType label_to_update = curr_label - 1;
-    size_t index_cap = index->indexCapacity();
+    size_t index_cap = index->indexMetaDataCapacity();
+    std::cout << "index_cap after adding vectors " << index_cap << std::endl;
+    assert(index_cap == initial_index_cap + BM_VecSimGeneral::block_size);
+
     for (auto _ : st) {
         // Remove the vector directly from hnsw
         size_t ret = VecSimIndex_DeleteVector(
             GET_INDEX(st.range(0) == INDEX_TIERED_HNSW ? INDEX_HNSW : st.range(0)),
             label_to_update);
         assert(ret == 1);
-        assert(index->indexCapacity() == index_cap - BM_VecSimGeneral::block_size);
-        // Capacity should shrink by one block after deletion
+
+        // Capacity should not change
+        size_t curr_cap = index->indexMetaDataCapacity();
+        assert(curr_cap == index_cap);
         ret = VecSimIndex_AddVector(index, QUERIES[(added_vec_count - 1) % N_QUERIES].data(),
                                     label_to_update);
         assert(ret == 1);
         BM_VecSimGeneral::mock_thread_pool->thread_pool_wait();
         assert(VecSimIndex_IndexSize(
                    GET_INDEX(st.range(0) == INDEX_TIERED_HNSW ? INDEX_HNSW : st.range(0))) ==
                N_VECTORS + added_vec_count);
-        // Capacity should grow back to original size after addition
-        assert(index->indexCapacity() == index_cap);
+        // Capacity should not change
+        assert(index->indexMetaDataCapacity() == index_cap);
     }
     assert(VecSimIndex_IndexSize(index) == N_VECTORS + added_vec_count);
 

tests/unit/test_allocator.cpp

@@ -126,6 +126,7 @@ TYPED_TEST(IndexAllocatorTest, test_bf_index_block_size_1) {
 
         ASSERT_EQ(bfIndex->indexCapacity(), expected_map_containers_size);
         ASSERT_EQ(bfIndex->idToLabelMapping.capacity(), expected_map_containers_size);
+        ASSERT_EQ(bfIndex->indexMetaDataCapacity(), expected_map_containers_size);
         ASSERT_EQ(bfIndex->idToLabelMapping.size(), expected_map_containers_size);
         ASSERT_GE(bfIndex->labelToIdLookup.bucket_count(), expected_map_containers_size);
     };
@@ -536,6 +537,7 @@ TYPED_TEST(IndexAllocatorTest, test_hnsw_reclaim_memory) {
         ASSERT_EQ(hnswIndex->vectors->size(), expected_size);
 
         ASSERT_EQ(hnswIndex->idToMetaData.capacity(), expected_map_containers_size);
+        ASSERT_EQ(hnswIndex->indexMetaDataCapacity(), expected_map_containers_size);
         ASSERT_EQ(hnswIndex->idToMetaData.size(), expected_map_containers_size);
         ASSERT_GE(hnswIndex->labelLookup.bucket_count(), expected_map_containers_size);
         // Also validate that there are no unidirectional connections (these add memory to the

tests/unit/test_hnsw_tiered.cpp

@@ -4364,6 +4364,11 @@ TYPED_TEST(HNSWTieredIndexTestBasic, HNSWResize) {
     ASSERT_EQ(tiered_index->getMainIndexGuardWriteLockCount(), resize_operations);
     ASSERT_EQ(hnsw_index->indexSize(), 1);
     ASSERT_EQ(hnsw_index->indexCapacity(), blockSize);
+    ASSERT_EQ(hnsw_index->indexMetaDataCapacity(), blockSize);
+    ASSERT_EQ(tiered_index->frontendIndex->indexMetaDataCapacity(), 0);
+    ASSERT_EQ(tiered_index->indexMetaDataCapacity(),
+              hnsw_index->indexMetaDataCapacity() +
+                  tiered_index->frontendIndex->indexMetaDataCapacity());
 
     // add up to block size
     for (size_t i = 1; i < blockSize; i++) {
@@ -4374,6 +4379,11 @@ TYPED_TEST(HNSWTieredIndexTestBasic, HNSWResize) {
     ASSERT_EQ(tiered_index->getMainIndexGuardWriteLockCount(), resize_operations);
     ASSERT_EQ(hnsw_index->indexSize(), blockSize);
     ASSERT_EQ(hnsw_index->indexCapacity(), blockSize);
+    ASSERT_EQ(hnsw_index->indexMetaDataCapacity(), blockSize);
+    ASSERT_EQ(tiered_index->frontendIndex->indexMetaDataCapacity(), 0);
+    ASSERT_EQ(tiered_index->indexMetaDataCapacity(),
+              hnsw_index->indexMetaDataCapacity() +
+                  tiered_index->frontendIndex->indexMetaDataCapacity());
 
     // add one more vector to trigger another resize
     GenerateAndAddVector<TEST_DATA_T>(tiered_index, dim, blockSize);
@@ -4383,6 +4393,11 @@ TYPED_TEST(HNSWTieredIndexTestBasic, HNSWResize) {
     ASSERT_EQ(tiered_index->getMainIndexGuardWriteLockCount(), resize_operations);
     ASSERT_EQ(hnsw_index->indexSize(), blockSize + 1);
     ASSERT_EQ(hnsw_index->indexCapacity(), 2 * blockSize);
+    ASSERT_EQ(hnsw_index->indexMetaDataCapacity(), 2 * blockSize);
+    ASSERT_EQ(tiered_index->frontendIndex->indexMetaDataCapacity(), 0);
+    ASSERT_EQ(tiered_index->indexMetaDataCapacity(),
+              hnsw_index->indexMetaDataCapacity() +
+                  tiered_index->frontendIndex->indexMetaDataCapacity());
 
     // delete a vector to shrink data blocks
     ASSERT_EQ(VecSimIndex_DeleteVector(tiered_index, 0), 1) << "Failed to delete vector 0";
@@ -4394,6 +4409,8 @@ TYPED_TEST(HNSWTieredIndexTestBasic, HNSWResize) {
     ASSERT_EQ(tiered_index->getMainIndexGuardWriteLockCount(), resize_operations);
     ASSERT_EQ(hnsw_index->indexSize(), blockSize);
     ASSERT_EQ(hnsw_index->indexCapacity(), blockSize);
+    // meta data capacity should not shrink
+    ASSERT_EQ(hnsw_index->indexMetaDataCapacity(), 2 * blockSize);
 
     // add this vector again and verify lock was acquired to resize
     GenerateAndAddVector<TEST_DATA_T>(tiered_index, dim, 0);
@@ -4402,6 +4419,11 @@ TYPED_TEST(HNSWTieredIndexTestBasic, HNSWResize) {
     ASSERT_EQ(tiered_index->getMainIndexGuardWriteLockCount(), resize_operations);
     ASSERT_EQ(hnsw_index->indexSize(), blockSize + 1);
     ASSERT_EQ(hnsw_index->indexCapacity(), 2 * blockSize);
+    ASSERT_EQ(hnsw_index->indexMetaDataCapacity(), 2 * blockSize);
+    ASSERT_EQ(tiered_index->frontendIndex->indexMetaDataCapacity(), 0);
+    ASSERT_EQ(tiered_index->indexMetaDataCapacity(),
+              hnsw_index->indexMetaDataCapacity() +
+                  tiered_index->frontendIndex->indexMetaDataCapacity());
 
     // add up to block size (count = 2 blockSize), the lock shouldn't be acquired because no resize
     // is required
@@ -4412,4 +4434,9 @@ TYPED_TEST(HNSWTieredIndexTestBasic, HNSWResize) {
     ASSERT_EQ(tiered_index->getMainIndexGuardWriteLockCount(), resize_operations);
     ASSERT_EQ(hnsw_index->indexSize(), 2 * blockSize);
     ASSERT_EQ(hnsw_index->indexCapacity(), 2 * blockSize);
+    ASSERT_EQ(hnsw_index->indexMetaDataCapacity(), 2 * blockSize);
+    ASSERT_EQ(tiered_index->frontendIndex->indexMetaDataCapacity(), 0);
+    ASSERT_EQ(tiered_index->indexMetaDataCapacity(),
+              hnsw_index->indexMetaDataCapacity() +
+                  tiered_index->frontendIndex->indexMetaDataCapacity());
 }

tests/unit/test_svs.cpp

@@ -833,6 +833,7 @@ TYPED_TEST(SVSTest, resizeIndex) {
     }
     // The size (+extra) and the capacity should be equal.
     ASSERT_EQ(index->indexCapacity(), VecSimIndex_IndexSize(index) + extra_cap);
+    ASSERT_EQ(index->indexMetaDataCapacity(), index->indexCapacity());
     // The capacity shouldn't be changed.
     ASSERT_EQ(index->indexCapacity(), n + extra_cap);
 
@@ -878,6 +879,7 @@ TYPED_TEST(SVSTest, svs_empty_index) {
 
     // The expected capacity should be 0 for empty index.
     ASSERT_EQ(index->indexCapacity(), 0);
+    ASSERT_EQ(index->indexMetaDataCapacity(), index->indexCapacity());
 
     // Try to remove it again.
     VecSimIndex_DeleteVector(index, 1);

tests/unit/test_svs_tiered.cpp

@@ -523,6 +523,7 @@ TYPED_TEST(SVSTieredIndexTest, addVector) {
     ASSERT_EQ(tiered_index->GetBackendIndex()->indexSize(), 0);
     ASSERT_EQ(tiered_index->GetFlatIndex()->indexCapacity(), DEFAULT_BLOCK_SIZE);
     ASSERT_EQ(tiered_index->indexCapacity(), DEFAULT_BLOCK_SIZE);
+    ASSERT_EQ(tiered_index->indexMetaDataCapacity(), tiered_index->indexCapacity());
     ASSERT_EQ(tiered_index->GetFlatIndex()->getDistanceFrom_Unsafe(vec_label, vector), 0);
     ASSERT_EQ(mock_thread_pool.jobQ.size(), mock_thread_pool.thread_pool_size);
 
@@ -624,6 +625,7 @@ TYPED_TEST(SVSTieredIndexTest, insertJob) {
                                          ? DEFAULT_BLOCK_SIZE
                                          : tiered_index->GetBackendIndex()->indexCapacity();
     ASSERT_EQ(tiered_index->indexCapacity(), expected_capacity);
+    ASSERT_EQ(tiered_index->indexMetaDataCapacity(), tiered_index->indexCapacity());
     ASSERT_EQ(tiered_index->GetFlatIndex()->indexCapacity(), 0);
     ASSERT_EQ(tiered_index->getDistanceFrom_Unsafe(vec_label, vector), 0);
 }