Add search::tensor::SubspaceType.

15 files changed, 105 insertions, 47 deletions

diff --git a/searchlib/src/tests/tensor/hnsw_index/hnsw_index_test.cpp b/searchlib/src/tests/tensor/hnsw_index/hnsw_index_test.cpp
index 9da2d8a4d5f..7a32511ff26 100644
--- a/searchlib/src/tests/tensor/hnsw_index/hnsw_index_test.cpp
+++ b/searchlib/src/tests/tensor/hnsw_index/hnsw_index_test.cpp
@@ -1,11 +1,13 @@
 // Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 
+#include <vespa/eval/eval/value_type.h>
 #include <vespa/searchlib/common/bitvector.h>
 #include <vespa/searchlib/tensor/distance_functions.h>
 #include <vespa/searchlib/tensor/doc_vector_access.h>
 #include <vespa/searchlib/tensor/hnsw_index.h>
 #include <vespa/searchlib/tensor/random_level_generator.h>
 #include <vespa/searchlib/tensor/inv_log_level_generator.h>
+#include <vespa/searchlib/tensor/subspace_type.h>
 #include <vespa/searchlib/tensor/vector_bundle.h>
 #include <vespa/searchlib/queryeval/global_filter.h>
 #include <vespa/vespalib/datastore/compaction_spec.h>
@@ -25,6 +27,7 @@ using namespace vespalib::slime;
 using vespalib::Slime;
 using search::BitVector;
 using vespalib::eval::get_cell_type;
+using vespalib::eval::ValueType;
 using vespalib::datastore::CompactionSpec;
 using vespalib::datastore::CompactionStrategy;
 using search::queryeval::GlobalFilter;
@@ -35,9 +38,14 @@ private:
     using Vector = std::vector<FloatType>;
     using ArrayRef = vespalib::ConstArrayRef<FloatType>;
     std::vector<Vector> _vectors;
+    SubspaceType        _subspace_type;
 
 public:
-    MyDocVectorAccess() : _vectors() {}
+    MyDocVectorAccess()
+        : _vectors(),
+          _subspace_type(ValueType::make_type(get_cell_type<FloatType>(), {{"dims", 2}}))
+    {
+    }
     MyDocVectorAccess& set(uint32_t docid, const Vector& vec) {
         if (docid >= _vectors.size()) {
             _vectors.resize(docid + 1);
@@ -52,7 +60,8 @@ public:
     }
     VectorBundle get_vectors(uint32_t docid) const override {
         ArrayRef ref(_vectors[docid]);
-        return VectorBundle(ref.data(), get_cell_type<FloatType>(), 1, ref.size() * sizeof(FloatType), ref.size());
+        assert(_subspace_type.size() == ref.size());
+        return VectorBundle(ref.data(), 1, _subspace_type);
     }
 
     void clear() { _vectors.clear(); }
diff --git a/searchlib/src/tests/tensor/hnsw_index/stress_hnsw_mt.cpp b/searchlib/src/tests/tensor/hnsw_index/stress_hnsw_mt.cpp
index 9a5f3a1627d..2a3f0b4af27 100644
--- a/searchlib/src/tests/tensor/hnsw_index/stress_hnsw_mt.cpp
+++ b/searchlib/src/tests/tensor/hnsw_index/stress_hnsw_mt.cpp
@@ -9,6 +9,7 @@
 #include <vector>
 
 #include <vespa/eval/eval/typed_cells.h>
+#include <vespa/eval/eval/value_type.h>
 #include <vespa/searchlib/common/bitvector.h>
 #include <vespa/searchlib/tensor/distance_functions.h>
 #include <vespa/searchlib/tensor/doc_vector_access.h>
@@ -33,6 +34,7 @@ using namespace search::tensor;
 using namespace vespalib::slime;
 using search::BitVector;
 using vespalib::eval::CellType;
+using vespalib::eval::ValueType;
 using vespalib::GenerationHandler;
 using vespalib::MemoryUsage;
 using vespalib::Slime;
@@ -42,6 +44,12 @@ using vespalib::Slime;
 #define NUM_POSSIBLE_DOCS 30000
 #define NUM_OPS 1000000
 
+namespace {
+
+SubspaceType subspace_type(ValueType::make_type(CellType::FLOAT, {{"dims", NUM_DIMS }}));
+
+}
+
 class RndGen {
 private:
     std::mt19937_64 urng;
@@ -121,7 +129,8 @@ public:
     VectorBundle get_vectors(uint32_t docid) const override {
         assert(docid < NUM_POSSIBLE_DOCS);
         ConstVectorRef ref(_vectors[docid]);
-        return VectorBundle(ref.data(), CellType::FLOAT, 1, sizeof(float) * NUM_DIMS, NUM_DIMS);
+        assert(subspace_type.size() == ref.size());
+        return VectorBundle(ref.data(), 1, subspace_type);
     }
 };
 
@@ -184,7 +193,8 @@ public:
             return result_promise.get_future();
         }
         void run() override {
-            VectorBundle v(vec.data(), CellType::FLOAT, 1, vec.size() * sizeof(float), vec.size());
+            assert(subspace_type.size() == vec.size());
+            VectorBundle v(vec.data(), 1, subspace_type);
             auto up = parent.index->prepare_add_document(docid, v, read_guard);
             result_promise.set_value(std::move(up));
         }
diff --git a/searchlib/src/vespa/searchlib/tensor/CMakeLists.txt b/searchlib/src/vespa/searchlib/tensor/CMakeLists.txt
index 2e8b619b2c4..bb2df40c368 100644
--- a/searchlib/src/vespa/searchlib/tensor/CMakeLists.txt
+++ b/searchlib/src/vespa/searchlib/tensor/CMakeLists.txt
@@ -28,6 +28,7 @@ vespa_add_library(searchlib_tensor OBJECT
     nearest_neighbor_index_saver.cpp
     serialized_fast_value_attribute.cpp
     small_subspaces_buffer_type.cpp
+    subspace_type.cpp
     tensor_attribute.cpp
     tensor_attribute_loader.cpp
     tensor_attribute_saver.cpp
diff --git a/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.cpp b/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.cpp
index 7ad4caade03..5cd5455bcac 100644
--- a/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.cpp
@@ -52,11 +52,7 @@ DenseTensorAttribute::prepare_set_tensor(DocId docid, const Value& tensor) const
             // With this optimization we avoid doing unnecessary costly work, first removing the vector point, then inserting the same point.
             return {};
         }
-        auto cells = tensor.cells();
-        auto& type = tensor.type();
-        auto cell_type = type.cell_type();
-        auto subspace_size = type.dense_subspace_size();
-        VectorBundle vectors(cells.data, cell_type, tensor.index().size(), vespalib::eval::CellTypeUtils::mem_size(cell_type, subspace_size), subspace_size);
+        VectorBundle vectors(tensor.cells().data, tensor.index().size(), _denseTensorStore.get_subspace_type());
         return _index->prepare_add_document(docid, vectors, getGenerationHandler().takeGuard());
     }
     return {};
diff --git a/searchlib/src/vespa/searchlib/tensor/dense_tensor_store.cpp b/searchlib/src/vespa/searchlib/tensor/dense_tensor_store.cpp
index c7327422f81..c373f6bdcd0 100644
--- a/searchlib/src/vespa/searchlib/tensor/dense_tensor_store.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/dense_tensor_store.cpp
@@ -1,6 +1,7 @@
 // Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 
 #include "dense_tensor_store.h"
+#include "subspace_type.h"
 #include <vespa/eval/eval/value.h>
 #include <vespa/vespalib/datastore/compacting_buffers.h>
 #include <vespa/vespalib/datastore/compaction_context.h>
@@ -79,7 +80,8 @@ DenseTensorStore::DenseTensorStore(const ValueType &type, std::shared_ptr<vespal
       _tensorSizeCalc(type),
       _bufferType(_tensorSizeCalc, std::move(allocator)),
       _type(type),
-      _empty(type)
+      _subspace_type(type),
+      _empty(_subspace_type)
 {
     _store.addType(&_bufferType);
     _store.init_primary_buffers();
diff --git a/searchlib/src/vespa/searchlib/tensor/dense_tensor_store.h b/searchlib/src/vespa/searchlib/tensor/dense_tensor_store.h
index 7b133977073..9e326e0ab1e 100644
--- a/searchlib/src/vespa/searchlib/tensor/dense_tensor_store.h
+++ b/searchlib/src/vespa/searchlib/tensor/dense_tensor_store.h
@@ -52,6 +52,7 @@ private:
     TensorSizeCalc _tensorSizeCalc;
     BufferType _bufferType;
     ValueType _type; // type of dense tensor
+    SubspaceType  _subspace_type;
     EmptySubspace _empty;
 public:
     DenseTensorStore(const ValueType &type, std::shared_ptr<vespalib::alloc::MemoryAllocator> allocator);
@@ -86,8 +87,9 @@ public:
         if (!ref.valid()) {
             return VectorBundle();
         }
-        return VectorBundle(getRawBuffer(ref), _type.cell_type(), 1, getBufSize(), getNumCells());
+        return VectorBundle(getRawBuffer(ref), 1, _subspace_type);
     }
+    const SubspaceType& get_subspace_type() const noexcept { return _subspace_type; }
     // The following method is meant to be used only for unit tests.
     uint32_t getArraySize() const { return _bufferType.getArraySize(); }
 };
diff --git a/searchlib/src/vespa/searchlib/tensor/direct_tensor_store.cpp b/searchlib/src/vespa/searchlib/tensor/direct_tensor_store.cpp
index cfc70cddb5c..fa13ab6303c 100644
--- a/searchlib/src/vespa/searchlib/tensor/direct_tensor_store.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/direct_tensor_store.cpp
@@ -53,7 +53,8 @@ DirectTensorStore::add_entry(TensorSP tensor)
 DirectTensorStore::DirectTensorStore(const vespalib::eval::ValueType& tensor_type)
     : TensorStore(_tensor_store),
       _tensor_store(std::make_unique<TensorBufferType>()),
-      _empty(tensor_type)
+      _subspace_type(tensor_type),
+      _empty(_subspace_type)
 {
     _tensor_store.enableFreeLists();
 }
diff --git a/searchlib/src/vespa/searchlib/tensor/direct_tensor_store.h b/searchlib/src/vespa/searchlib/tensor/direct_tensor_store.h
index a84c321c13a..01084e89776 100644
--- a/searchlib/src/vespa/searchlib/tensor/direct_tensor_store.h
+++ b/searchlib/src/vespa/searchlib/tensor/direct_tensor_store.h
@@ -4,6 +4,7 @@
 
 #include "tensor_store.h"
 #include "empty_subspace.h"
+#include "subspace_type.h"
 #include "vector_bundle.h"
 #include <vespa/eval/eval/value.h>
 #include <vespa/vespalib/datastore/datastore.h>
@@ -35,6 +36,7 @@ private:
     };
 
     TensorStoreType _tensor_store;
+    SubspaceType    _subspace_type;
     EmptySubspace   _empty;
 
     EntryRef add_entry(TensorSP tensor);
@@ -68,9 +70,7 @@ public:
         if (tensor == nullptr) {
             return VectorBundle();
         }
-        auto type = tensor->type();
-        auto subspace_size = type.dense_subspace_size();
-        return VectorBundle(tensor->cells().data, type.cell_type(), tensor->index().size(), vespalib::eval::CellTypeUtils::mem_size(type.cell_type(), subspace_size), subspace_size);
+        return VectorBundle(tensor->cells().data, tensor->index().size(), _subspace_type);
     }
 };
 
diff --git a/searchlib/src/vespa/searchlib/tensor/empty_subspace.cpp b/searchlib/src/vespa/searchlib/tensor/empty_subspace.cpp
index c225a6082f5..38ed3bd3bdf 100644
--- a/searchlib/src/vespa/searchlib/tensor/empty_subspace.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/empty_subspace.cpp
@@ -1,18 +1,16 @@
 // Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 
 #include "empty_subspace.h"
-#include <vespa/eval/eval/value_type.h>
+#include "subspace_type.h"
 
 namespace search::tensor {
 
-EmptySubspace::EmptySubspace(const vespalib::eval::ValueType& type)
+EmptySubspace::EmptySubspace(const SubspaceType& type)
     : _empty_space(),
       _cells()
 {
-    auto dense_subspace_size = type.dense_subspace_size();
-    auto cell_type = type.cell_type();
-    _empty_space.resize(vespalib::eval::CellTypeUtils::mem_size(cell_type, dense_subspace_size), 0);
-    _cells = vespalib::eval::TypedCells(&_empty_space[0], cell_type, dense_subspace_size);
+    _empty_space.resize(type.mem_size()),
+        _cells = vespalib::eval::TypedCells(&_empty_space[0], type.cell_type(), type.size());
 }
 
 EmptySubspace::~EmptySubspace() = default;
diff --git a/searchlib/src/vespa/searchlib/tensor/empty_subspace.h b/searchlib/src/vespa/searchlib/tensor/empty_subspace.h
index 8e58e35712f..017486bc643 100644
--- a/searchlib/src/vespa/searchlib/tensor/empty_subspace.h
+++ b/searchlib/src/vespa/searchlib/tensor/empty_subspace.h
@@ -5,10 +5,10 @@
 #include <vespa/eval/eval/typed_cells.h>
 #include <vector>
 
-namespace vespalib::eval { class ValueType; }
-
 namespace search::tensor {
 
+class SubspaceType;
+
 /*
  * Class containg an empty subspace, used as a bad fallback when we cannot
  * get a real subspace.
@@ -18,7 +18,7 @@ class EmptySubspace
     std::vector<char>          _empty_space;
     vespalib::eval::TypedCells _cells;
 public:
-    EmptySubspace(const vespalib::eval::ValueType& type);
+    explicit EmptySubspace(const SubspaceType& type);
     ~EmptySubspace();
     const vespalib::eval::TypedCells& cells() const noexcept { return _cells; }
 };
diff --git a/searchlib/src/vespa/searchlib/tensor/subspace_type.cpp b/searchlib/src/vespa/searchlib/tensor/subspace_type.cpp
new file mode 100644
index 00000000000..187af7531af
--- /dev/null
+++ b/searchlib/src/vespa/searchlib/tensor/subspace_type.cpp
@@ -0,0 +1,15 @@
+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "subspace_type.h"
+#include <vespa/eval/eval/value_type.h>
+
+namespace search::tensor {
+
+SubspaceType::SubspaceType(const vespalib::eval::ValueType& type)
+    : _cell_type(type.cell_type()),
+      _size(type.dense_subspace_size()),
+      _mem_size(vespalib::eval::CellTypeUtils::mem_size(_cell_type, _size))
+{
+}
+
+}
diff --git a/searchlib/src/vespa/searchlib/tensor/subspace_type.h b/searchlib/src/vespa/searchlib/tensor/subspace_type.h
new file mode 100644
index 00000000000..88520723155
--- /dev/null
+++ b/searchlib/src/vespa/searchlib/tensor/subspace_type.h
@@ -0,0 +1,26 @@
+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include <vespa/eval/eval/cell_type.h>
+
+namespace vespalib::eval { class ValueType; }
+
+namespace search::tensor {
+
+/*
+ * Class describing the type of a dense subspace in a tensor.
+ */
+class SubspaceType
+{
+    vespalib::eval::CellType _cell_type;
+    size_t                   _size;     // # cells
+    size_t                   _mem_size; // # bytes
+public:
+    explicit SubspaceType(const vespalib::eval::ValueType& type);
+    vespalib::eval::CellType cell_type() const noexcept { return _cell_type; }
+    size_t size() const noexcept { return _size; }
+    size_t mem_size() const noexcept { return _mem_size; }
+};
+
+}
diff --git a/searchlib/src/vespa/searchlib/tensor/tensor_buffer_operations.cpp b/searchlib/src/vespa/searchlib/tensor/tensor_buffer_operations.cpp
index 3a861552d80..4f0db54ac2a 100644
--- a/searchlib/src/vespa/searchlib/tensor/tensor_buffer_operations.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/tensor_buffer_operations.cpp
@@ -68,14 +68,12 @@ FastValueView::FastValueView(const ValueType& type, ConstArrayRef<string_id> lab
 }
 
 TensorBufferOperations::TensorBufferOperations(const vespalib::eval::ValueType& tensor_type)
-    : _num_mapped_dimensions(tensor_type.count_mapped_dimensions()),
-      _cell_mem_size(vespalib::eval::CellTypeUtils::mem_size(tensor_type.cell_type(), 1u)),
-      _min_alignment(adjust_min_alignment(vespalib::eval::CellTypeUtils::alignment(tensor_type.cell_type()))),
-      _dense_subspace_size(tensor_type.dense_subspace_size()),
-      _cell_type(tensor_type.cell_type()),
+    : _subspace_type(tensor_type),
+      _num_mapped_dimensions(tensor_type.count_mapped_dimensions()),
+      _min_alignment(adjust_min_alignment(vespalib::eval::CellTypeUtils::alignment(_subspace_type.cell_type()))),
       _addr(_num_mapped_dimensions),
       _addr_refs(),
-      _empty(tensor_type)
+      _empty(_subspace_type)
 {
     _addr_refs.reserve(_addr.size());
     for (auto& label : _addr) {
@@ -106,8 +104,8 @@ TensorBufferOperations::store_tensor(ArrayRef<char> buf, const vespalib::eval::V
     uint32_t num_subspaces = tensor.index().size();
     assert(num_subspaces <= num_subspaces_mask);
     auto labels_end_offset = get_labels_offset() + get_labels_mem_size(num_subspaces);
-    auto cells_size = num_subspaces * _dense_subspace_size;
-    auto cells_mem_size = cells_size * _cell_mem_size; // Size measured in bytes
+    auto cells_size = num_subspaces * _subspace_type.size();
+    auto cells_mem_size = num_subspaces * _subspace_type.mem_size(); // Size measured in bytes
     auto aligner = select_aligner(cells_mem_size);
     auto cells_start_offset = aligner.align(labels_end_offset);
     auto cells_end_offset = cells_start_offset + cells_mem_size;
@@ -148,11 +146,11 @@ TensorBufferOperations::make_fast_view(ConstArrayRef<char> buf, const vespalib::
     auto num_subspaces = get_num_subspaces(buf);
     assert(buf.size() >= get_array_size(num_subspaces));
     ConstArrayRef<string_id> labels(reinterpret_cast<const string_id*>(buf.data() + get_labels_offset()), num_subspaces * _num_mapped_dimensions);
-    auto cells_size = num_subspaces * _dense_subspace_size;
-    auto cells_mem_size = cells_size * _cell_mem_size; // Size measured in bytes
+    auto cells_size = num_subspaces * _subspace_type.size();
+    auto cells_mem_size = num_subspaces * _subspace_type.mem_size(); // Size measured in bytes
     auto aligner = select_aligner(cells_mem_size);
     auto cells_start_offset = get_cells_offset(num_subspaces, aligner);
-    TypedCells cells(buf.data() + cells_start_offset, _cell_type, cells_size);
+    TypedCells cells(buf.data() + cells_start_offset, _subspace_type.cell_type(), cells_size);
     assert(cells_start_offset + cells_mem_size <= buf.size());
     return std::make_unique<FastValueView>(tensor_type, labels, cells, _num_mapped_dimensions, num_subspaces);
 }
@@ -187,11 +185,11 @@ TensorBufferOperations::encode_stored_tensor(ConstArrayRef<char> buf, const vesp
     auto num_subspaces = get_num_subspaces(buf);
     assert(buf.size() >= get_array_size(num_subspaces));
     ConstArrayRef<string_id> labels(reinterpret_cast<const string_id*>(buf.data() + get_labels_offset()), num_subspaces * _num_mapped_dimensions);
-    auto cells_size = num_subspaces * _dense_subspace_size;
-    auto cells_mem_size = cells_size * _cell_mem_size; // Size measured in bytes
+    auto cells_size = num_subspaces * _subspace_type.size();
+    auto cells_mem_size = num_subspaces * _subspace_type.mem_size(); // Size measured in bytes
     auto aligner = select_aligner(cells_mem_size);
     auto cells_start_offset = get_cells_offset(num_subspaces, aligner);
-    TypedCells cells(buf.data() + cells_start_offset, _cell_type, cells_size);
+    TypedCells cells(buf.data() + cells_start_offset, _subspace_type.cell_type(), cells_size);
     assert(cells_start_offset + cells_mem_size <= buf.size());
     StringIdVector labels_copy(labels.begin(), labels.end());
     StreamedValueView streamed_value_view(tensor_type, _num_mapped_dimensions, cells, num_subspaces, labels_copy);
diff --git a/searchlib/src/vespa/searchlib/tensor/tensor_buffer_operations.h b/searchlib/src/vespa/searchlib/tensor/tensor_buffer_operations.h
index 43463e50ff1..26cf9a429a1 100644
--- a/searchlib/src/vespa/searchlib/tensor/tensor_buffer_operations.h
+++ b/searchlib/src/vespa/searchlib/tensor/tensor_buffer_operations.h
@@ -3,6 +3,7 @@
 #pragma once
 
 #include "empty_subspace.h"
+#include "subspace_type.h"
 #include "vector_bundle.h"
 #include <vespa/vespalib/datastore/aligner.h>
 #include <vespa/vespalib/util/arrayref.h>
@@ -39,11 +40,9 @@ namespace search::tensor {
  */
 class TensorBufferOperations
 {
+    SubspaceType                      _subspace_type;
     uint32_t                          _num_mapped_dimensions;
-    uint32_t                          _cell_mem_size;
     uint32_t                          _min_alignment;
-    size_t                            _dense_subspace_size;
-    vespalib::eval::CellType          _cell_type;
     std::vector<vespalib::string_id>  _addr;
     std::vector<vespalib::string_id*> _addr_refs;
     EmptySubspace                     _empty;
@@ -58,7 +57,7 @@ class TensorBufferOperations
     static constexpr size_t get_num_subspaces_size() noexcept { return sizeof(uint32_t); }
     static constexpr size_t get_labels_offset() noexcept { return get_num_subspaces_size(); }
     size_t get_cells_mem_size(uint32_t num_subspaces) const noexcept {
-        return _dense_subspace_size * _cell_mem_size * num_subspaces;
+        return _subspace_type.mem_size() * num_subspaces;
     }
     auto select_aligner(size_t cells_mem_size) const noexcept {
         return Aligner((cells_mem_size < CELLS_ALIGNMENT_MEM_SIZE_MIN) ? _min_alignment : CELLS_ALIGNMENT);
@@ -108,7 +107,7 @@ public:
         auto num_subspaces = get_num_subspaces(buf);
         auto cells_mem_size = get_cells_mem_size(num_subspaces);
         auto aligner = select_aligner(cells_mem_size);
-        return VectorBundle(buf.data() + get_cells_offset(num_subspaces, aligner), _cell_type, num_subspaces, _dense_subspace_size * _cell_mem_size, _dense_subspace_size);
+        return VectorBundle(buf.data() + get_cells_offset(num_subspaces, aligner), num_subspaces, _subspace_type);
     }
 };
 
diff --git a/searchlib/src/vespa/searchlib/tensor/vector_bundle.h b/searchlib/src/vespa/searchlib/tensor/vector_bundle.h
index cb1d3f99cfb..09d0b514954 100644
--- a/searchlib/src/vespa/searchlib/tensor/vector_bundle.h
+++ b/searchlib/src/vespa/searchlib/tensor/vector_bundle.h
@@ -2,6 +2,7 @@
 
 #pragma once
 
+#include "subspace_type.h"
 #include <vespa/eval/eval/typed_cells.h>
 #include <cassert>
 
@@ -27,12 +28,12 @@ public:
           _subspace_size(0)
     {
     }
-    VectorBundle(const void *data, vespalib::eval::CellType cell_type, uint32_t subspaces, size_t subspace_mem_size, size_t subspace_size)
+    VectorBundle(const void *data, uint32_t subspaces, const SubspaceType& subspace_type)
         : _data(data),
-          _cell_type(cell_type),
+          _cell_type(subspace_type.cell_type()),
           _subspaces(subspaces),
-          _subspace_mem_size(subspace_mem_size),
-          _subspace_size(subspace_size)
+          _subspace_mem_size(subspace_type.mem_size()),
+          _subspace_size(subspace_type.size())
     {
     }
     ~VectorBundle() = default;