diff --git a/source/blender/blenkernel/intern/mesh_mapping.cc b/source/blender/blenkernel/intern/mesh_mapping.cc
index 942b755975e..1b3220fe497 100644
--- a/source/blender/blenkernel/intern/mesh_mapping.cc
+++ b/source/blender/blenkernel/intern/mesh_mapping.cc
@@ -11,6 +11,8 @@
 
 #include "MEM_guardedalloc.h"
 
+#include "atomic_ops.h"
+
 #include "DNA_meshdata_types.h"
 #include "DNA_vec_types.h"
 
@@ -306,6 +308,52 @@ static Array<int> create_reverse_offsets(const Span<int> indices, const int item
   return offsets;
 }
 
+static void sort_small_groups(const OffsetIndices<int> groups,
+                              const int grain_size,
+                              MutableSpan<int> indices)
+{
+  threading::parallel_for(groups.index_range(), grain_size, [&](const IndexRange range) {
+    for (const int64_t index : range) {
+      MutableSpan<int> group = indices.slice(groups[index]);
+      std::sort(group.begin(), group.end());
+    }
+  });
+}
+
+static Array<int> reverse_indices_in_groups(const Span<int> group_indices,
+                                            const OffsetIndices<int> offsets)
+{
+  BLI_assert(!group_indices.is_empty());
+  BLI_assert(*std::max_element(group_indices.begin(), group_indices.end()) < offsets.size());
+  BLI_assert(*std::min_element(group_indices.begin(), group_indices.end()) >= 0);
+  Array<int> counts(offsets.size(), -1);
+  Array<int> results(group_indices.size());
+  threading::parallel_for(group_indices.index_range(), 1024, [&](const IndexRange range) {
+    for (const int64_t i : range) {
+      const int group_index = group_indices[i];
+      const int index_in_group = atomic_add_and_fetch_int32(&counts[group_index], 1);
+      results[offsets[group_index][index_in_group]] = int(i);
+    }
+  });
+  sort_small_groups(offsets, 1024, results);
+  return results;
+}
+
+static GroupedSpan<int> gather_groups(const Span<int> group_indices,
+                                      const int groups_num,
+                                      Array<int> &r_offsets,
+                                      Array<int> &r_indices)
+{
+  if (group_indices.is_empty()) {
+    r_offsets.reinitialize(groups_num + 1);
+    r_offsets.as_mutable_span().fill(0);
+    return {OffsetIndices<int>(r_offsets), {}};
+  }
+  r_offsets = create_reverse_offsets(group_indices, groups_num);
+  r_indices = reverse_indices_in_groups(group_indices, r_offsets.as_span());
+  return {OffsetIndices<int>(r_offsets), r_indices};
+}
+
 Array<int> build_loop_to_face_map(const OffsetIndices<int> faces)
 {
   Array<int> map(faces.total_size());
@@ -355,16 +403,7 @@ GroupedSpan<int> build_vert_to_loop_map(const Span<int> corner_verts,
                                         Array<int> &r_offsets,
                                         Array<int> &r_indices)
 {
-  r_offsets = create_reverse_offsets(corner_verts, verts_num);
-  r_indices.reinitialize(r_offsets.last());
-  Array<int> counts(verts_num, 0);
-
-  for (const int64_t corner : corner_verts.index_range()) {
-    const int vert = corner_verts[corner];
-    r_indices[r_offsets[vert] + counts[vert]] = int(corner);
-    counts[vert]++;
-  }
-  return {OffsetIndices<int>(r_offsets), r_indices};
+  return gather_groups(corner_verts, verts_num, r_offsets, r_indices);
 }
 
 GroupedSpan<int> build_edge_to_loop_map(const Span<int> corner_edges,
@@ -372,16 +411,7 @@ GroupedSpan<int> build_edge_to_loop_map(const Span<int> corner_edges,
                                         Array<int> &r_offsets,
                                         Array<int> &r_indices)
 {
-  r_offsets = create_reverse_offsets(corner_edges, edges_num);
-  r_indices.reinitialize(r_offsets.last());
-  Array<int> counts(edges_num, 0);
-
-  for (const int64_t corner : corner_edges.index_range()) {
-    const int edge = corner_edges[corner];
-    r_indices[r_offsets[edge] + counts[edge]] = int(corner);
-    counts[edge]++;
-  }
-  return {OffsetIndices<int>(r_offsets), r_indices};
+  return gather_groups(corner_edges, edges_num, r_offsets, r_indices);
 }
 
 GroupedSpan<int> build_edge_to_face_map(const OffsetIndices<int> faces,