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src/storage/v3/splitter.cpp

@@ -68,7 +68,6 @@ VertexContainer Splitter::CollectVertices(SplitData &data, std::set<uint64_t> &c
                                           const PrimaryKey &split_key) {
   // Collection of indices is here since it heavily depends on vertices
   // Old vertex pointer new entry pointer
-
   std::map<LabelId, std::multimap<const Vertex *, const LabelIndex::IndexContainer::iterator>>
       label_index_vertex_entry_map;
   std::map<std::pair<LabelId, PropertyId>,
@@ -79,6 +78,7 @@ VertexContainer Splitter::CollectVertices(SplitData &data, std::set<uint64_t> &c
       CollectIndexEntries<LabelIndex, LabelId>(indices_.label_index, split_key, label_index_vertex_entry_map);
   data.label_property_indices = CollectIndexEntries<LabelPropertyIndex, std::pair<LabelId, PropertyId>>(
       indices_.label_property_index, split_key, label_property_vertex_entry_map);
+  // This is needed to replace old vertex pointers in index entries with new ones
   const auto update_indices = [](auto &entry_vertex_map, auto &updating_index, const auto *old_vertex_ptr,
                                  auto &new_vertex_ptr) {
     for ([[maybe_unused]] auto &[index_type, vertex_entry_mappings] : entry_vertex_map) {
@@ -96,7 +96,7 @@ VertexContainer Splitter::CollectVertices(SplitData &data, std::set<uint64_t> &c
   VertexContainer splitted_data;
   auto split_key_it = vertices_.find(split_key);
   while (split_key_it != vertices_.end()) {
-    // Go through deltas and pick up transactions start_id
+    // Go through deltas and pick up transactions start_id/commit_id
     ScanDeltas(collected_transactions_, split_key_it->second.delta);
 
     const auto *old_vertex_ptr = &*split_key_it;
@@ -107,7 +107,7 @@ VertexContainer Splitter::CollectVertices(SplitData &data, std::set<uint64_t> &c
 
     // Update indices
     update_indices(label_index_vertex_entry_map, data.label_indices, old_vertex_ptr, splitted_vertex_it);
-    // update_indices(label_property_vertex_entry_map, old_vertex_ptr, splitted_vertex_it);
+    update_indices(label_property_vertex_entry_map, data.label_property_indices, old_vertex_ptr, splitted_vertex_it);
 
     split_key_it = next_it;
   }
@@ -122,14 +122,13 @@ std::optional<EdgeContainer> Splitter::CollectEdges(std::set<uint64_t> &collecte
   }
   EdgeContainer splitted_edges;
   const auto split_vertex_edges = [&](const auto &edges_ref) {
-    // This is safe since if properties_on_edges is true, the this must be a
+    // This is safe since if properties_on_edges is true, the this must be a ptr
-    // ptr
     for (const auto &edge_ref : edges_ref) {
       auto *edge = std::get<2>(edge_ref).ptr;
       const auto &other_vtx = std::get<1>(edge_ref);
       ScanDeltas(collected_transactions_, edge->delta);
-      // Check if src and dest edge are both on splitted shard
+      // Check if src and dest edge are both on splitted shard so we know if we
-      // so we know if we should remove orphan edge
+      // should remove orphan edge, or make a clone
       if (other_vtx.primary_key >= split_key) {
         // Remove edge from shard
         splitted_edges.insert(edges_.extract(edge->gid));
@@ -183,8 +182,7 @@ void Splitter::AdjustClonedTransaction(Transaction &cloned_transaction, const Tr
     const auto *delta = &*delta_it;
     auto *cloned_delta = &*cloned_delta_it;
     while (delta != nullptr) {
-      // Align delta, while ignoring deltas whose transactions have commited,
+      // Align deltas which belong to cloned transaction, skip others
-      // or aborted
       if (cloned_transactions.contains(delta->commit_info->start_or_commit_timestamp.logical_id)) {
         auto *found_delta_it = &*std::ranges::find_if(
             cloned_transactions.at(delta->commit_info->start_or_commit_timestamp.logical_id)->deltas,
@@ -208,7 +206,8 @@ void Splitter::AdjustClonedTransaction(Transaction &cloned_transaction, const Tr
         }
         case PreviousPtr::Type::VERTEX: {
           // What if the vertex is already moved to garbage collection...
-          // Make test when you have deleted vertex
+          // TODO(jbajic) Maybe revisit when we apply Garbage collection with new
+          // transaction management system
           auto *cloned_vertex = &*cloned_vertices.find(ptr.vertex->first);
           cloned_delta->prev.Set(cloned_vertex);
           break;

src/storage/v3/splitter.hpp

@@ -81,17 +81,16 @@ class Splitter final {
       return {};
     }
 
+    // Cloned index entries will contain new index entry iterators, but old
+    // vertices address which need to be adjusted after extracting vertices
     std::map<IndexType, typename IndexMap::IndexContainer> cloned_indices;
     for (auto &[index_type_val, index] : index.GetIndex()) {
-      // cloned_indices[index_type_val] = typename IndexMap::IndexContainer{};
-
       auto entry_it = index.begin();
       while (entry_it != index.end()) {
         // We need to save the next pointer since the current one will be
         // invalidated after extract
         auto next_entry_it = std::next(entry_it);
         if (entry_it->vertex->first > split_key) {
-          // We get this entry
           [[maybe_unused]] const auto &[inserted_entry_it, inserted, node] =
               cloned_indices[index_type_val].insert(index.extract(entry_it));
           MG_ASSERT(inserted, "Failed to extract index entry!");