From 885519782cac6d7375b45c5e4494c524b1f9e4dd Mon Sep 17 00:00:00 2001
From: achirkin <achirkin@users.noreply.github.com>
Date: Fri, 24 Nov 2023 15:26:40 +0100
Subject: [PATCH] Add ANN.copy support to cagra_hnswlib wrapper

---
 .../ann/src/raft/raft_cagra_hnswlib_wrapper.h | 56 ++++++++-----------
 1 file changed, 22 insertions(+), 34 deletions(-)

diff --git a/cpp/bench/ann/src/raft/raft_cagra_hnswlib_wrapper.h b/cpp/bench/ann/src/raft/raft_cagra_hnswlib_wrapper.h
index e42cb5e7f2..3fd0a374b7 100644
--- a/cpp/bench/ann/src/raft/raft_cagra_hnswlib_wrapper.h
+++ b/cpp/bench/ann/src/raft/raft_cagra_hnswlib_wrapper.h
@@ -30,15 +30,12 @@ class RaftCagraHnswlib : public ANN<T> {
 
   RaftCagraHnswlib(Metric metric, int dim, const BuildParam& param, int concurrent_searches = 1)
     : ANN<T>(metric, dim),
-      metric_(metric),
-      index_params_(param),
-      dimension_(dim),
-      handle_(cudaStreamPerThread)
+      cagra_build_{metric, dim, param, concurrent_searches},
+      // HnswLib param values don't matter since we don't build with HnswLib
+      hnswlib_search_{metric, dim, typename HnswLib<T>::BuildParam{50, 100}}
   {
   }
 
-  ~RaftCagraHnswlib() noexcept {}
-
   void build(const T* dataset, size_t nrow, cudaStream_t stream) final;
 
   void set_search_param(const AnnSearchParam& param) override;
@@ -60,62 +57,53 @@ class RaftCagraHnswlib : public ANN<T> {
     property.query_memory_type   = MemoryType::Host;
     return property;
   }
+
   void save(const std::string& file) const override;
   void load(const std::string&) override;
-  std::unique_ptr<ANN<T>> copy() override;
+  std::unique_ptr<ANN<T>> copy() override
+  {
+    return std::make_unique<RaftCagraHnswlib<T, IdxT>>(*this);
+  }
 
  private:
-  raft::device_resources handle_;
-  Metric metric_;
-  BuildParam index_params_;
-  int dimension_;
-
-  std::unique_ptr<RaftCagra<T, IdxT>> cagra_build_;
-  std::unique_ptr<HnswLib<T>> hnswlib_search_;
-
-  Objective metric_objective_;
+  RaftCagra<T, IdxT> cagra_build_;
+  HnswLib<T> hnswlib_search_;
 };
 
 template <typename T, typename IdxT>
 void RaftCagraHnswlib<T, IdxT>::build(const T* dataset, size_t nrow, cudaStream_t stream)
 {
-  if (not cagra_build_) {
-    cagra_build_ = std::make_unique<RaftCagra<T, IdxT>>(metric_, dimension_, index_params_);
-  }
-  cagra_build_->build(dataset, nrow, stream);
+  cagra_build_.build(dataset, nrow, stream);
 }
 
 template <typename T, typename IdxT>
 void RaftCagraHnswlib<T, IdxT>::set_search_param(const AnnSearchParam& param_)
 {
-  hnswlib_search_->set_search_param(param_);
+  hnswlib_search_.set_search_param(param_);
 }
 
 template <typename T, typename IdxT>
 void RaftCagraHnswlib<T, IdxT>::save(const std::string& file) const
 {
-  cagra_build_->save_to_hnswlib(file);
+  cagra_build_.save_to_hnswlib(file);
 }
 
 template <typename T, typename IdxT>
 void RaftCagraHnswlib<T, IdxT>::load(const std::string& file)
 {
-  typename HnswLib<T>::BuildParam param;
-  // these values don't matter since we don't build with HnswLib
-  param.M               = 50;
-  param.ef_construction = 100;
-  if (not hnswlib_search_) {
-    hnswlib_search_ = std::make_unique<HnswLib<T>>(metric_, dimension_, param);
-  }
-  hnswlib_search_->load(file);
-  hnswlib_search_->set_base_layer_only();
+  hnswlib_search_.load(file);
+  hnswlib_search_.set_base_layer_only();
 }
 
 template <typename T, typename IdxT>
-void RaftCagraHnswlib<T, IdxT>::search(
-  const T* queries, int batch_size, int k, size_t* neighbors, float* distances, cudaStream_t) const
+void RaftCagraHnswlib<T, IdxT>::search(const T* queries,
+                                       int batch_size,
+                                       int k,
+                                       size_t* neighbors,
+                                       float* distances,
+                                       cudaStream_t stream) const
 {
-  hnswlib_search_->search(queries, batch_size, k, neighbors, distances);
+  hnswlib_search_.search(queries, batch_size, k, neighbors, distances, stream);
 }
 
 }  // namespace raft::bench::ann