Add hnsw search params for bounded queue option (#3748)

Summary:
Pull Request resolved: #3748

So we can dynamically change it

Reviewed By: asadoughi

Differential Revision: D61029191

fbshipit-source-id: 19a6775c1218762dac7a7805e13efab9bb43cfa5

faiss/impl/HNSW.cpp

@@ -847,6 +847,9 @@ HNSWStats HNSW::search(
     }
     int k = extract_k_from_ResultHandler(res);
 
+    bool bounded_queue =
+            params ? params->bounded_queue : this->search_bounded_queue;
+
     if (upper_beam == 1) {
         //  greedy search on upper levels
         storage_idx_t nearest = entry_point;
@@ -857,7 +860,7 @@ HNSWStats HNSW::search(
         }
 
         int ef = std::max(params ? params->efSearch : efSearch, k);
-        if (search_bounded_queue) { // this is the most common branch
+        if (bounded_queue) { // this is the most common branch
             MinimaxHeap candidates(ef);
 
             candidates.push(nearest, d_nearest);

faiss/impl/HNSW.h

@@ -46,6 +46,7 @@ struct ResultHandler;
 struct SearchParametersHNSW : SearchParameters {
     int efSearch = 16;
     bool check_relative_distance = true;
+    bool bounded_queue = true;
 
     ~SearchParametersHNSW() {}
 };