Merge pull request #24410 from vespa-engine/geirst/align-terminology-generation-hold-lists

Align terminology on generation hold lists in attribute vector code

42 files changed, 141 insertions, 143 deletions

diff --git a/searchcore/src/vespa/searchcore/proton/documentmetastore/documentmetastore.cpp b/searchcore/src/vespa/searchcore/proton/documentmetastore/documentmetastore.cpp
index c6ef6994b81..ead9f142508 100644
--- a/searchcore/src/vespa/searchcore/proton/documentmetastore/documentmetastore.cpp
+++ b/searchcore/src/vespa/searchcore/proton/documentmetastore/documentmetastore.cpp
@@ -241,20 +241,20 @@ DocumentMetaStore::onUpdateStat()
 }
 
 void
-DocumentMetaStore::onGenerationChange(generation_t generation)
+DocumentMetaStore::before_inc_generation(generation_t current_gen)
 {
     _gidToLidMap.getAllocator().freeze();
-    _gidToLidMap.getAllocator().assign_generation(generation - 1);
-    getGenerationHolder().assign_generation(generation - 1);
+    _gidToLidMap.getAllocator().assign_generation(current_gen);
+    getGenerationHolder().assign_generation(current_gen);
     updateStat(false);
 }
 
 void
-DocumentMetaStore::removeOldGenerations(generation_t firstUsed)
+DocumentMetaStore::reclaim_memory(generation_t oldest_used_gen)
 {
-    _gidToLidMap.getAllocator().reclaim_memory(firstUsed);
-    _lidAlloc.reclaim_memory(firstUsed);
-    getGenerationHolder().reclaim(firstUsed);
+    _gidToLidMap.getAllocator().reclaim_memory(oldest_used_gen);
+    _lidAlloc.reclaim_memory(oldest_used_gen);
+    getGenerationHolder().reclaim(oldest_used_gen);
 }
 
 std::unique_ptr<search::AttributeSaver>
diff --git a/searchcore/src/vespa/searchcore/proton/documentmetastore/documentmetastore.h b/searchcore/src/vespa/searchcore/proton/documentmetastore/documentmetastore.h
index c4010a07709..2dc85f07cf4 100644
--- a/searchcore/src/vespa/searchcore/proton/documentmetastore/documentmetastore.h
+++ b/searchcore/src/vespa/searchcore/proton/documentmetastore/documentmetastore.h
@@ -93,8 +93,8 @@ private:
     void onUpdateStat() override;
 
     // Implements AttributeVector
-    void onGenerationChange(generation_t generation) override;
-    void removeOldGenerations(generation_t firstUsed) override;
+    void before_inc_generation(generation_t current_gen) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
     std::unique_ptr<search::AttributeSaver> onInitSave(vespalib::stringref fileName) override;
     bool onLoad(vespalib::Executor *executor) override;
 
diff --git a/searchlib/src/tests/attribute/multi_value_mapping/multi_value_mapping_test.cpp b/searchlib/src/tests/attribute/multi_value_mapping/multi_value_mapping_test.cpp
index 938a7fb35d7..8b8f4d2c4d4 100644
--- a/searchlib/src/tests/attribute/multi_value_mapping/multi_value_mapping_test.cpp
+++ b/searchlib/src/tests/attribute/multi_value_mapping/multi_value_mapping_test.cpp
@@ -41,11 +41,11 @@ class MyAttribute : public search::NotImplementedAttribute
         _mvMapping.shrink(committedDocIdLimit);
         setNumDocs(committedDocIdLimit);
     }
-    virtual void removeOldGenerations(generation_t firstUsed) override {
-        _mvMapping.reclaim_memory(firstUsed);
+    virtual void reclaim_memory(generation_t oldest_used_gen) override {
+        _mvMapping.reclaim_memory(oldest_used_gen);
     }
-    virtual void onGenerationChange(generation_t generation) override {
-        _mvMapping.assign_generation(generation - 1);
+    virtual void before_inc_generation(generation_t current_gen) override {
+        _mvMapping.assign_generation(current_gen);
     }
 
 public:
diff --git a/searchlib/src/tests/attribute/postinglist/postinglist.cpp b/searchlib/src/tests/attribute/postinglist/postinglist.cpp
index e41aaec351e..1eed3a015e1 100644
--- a/searchlib/src/tests/attribute/postinglist/postinglist.cpp
+++ b/searchlib/src/tests/attribute/postinglist/postinglist.cpp
@@ -201,7 +201,7 @@ private:
                    PostingListNodeAllocator &postingsAlloc);
 
     void
-    removeOldGenerations(Tree &tree,
+    reclaim_memory(Tree &tree,
                          ValueHandle &valueHandle,
                          PostingList &postings,
                          PostingListNodeAllocator &postingsAlloc);
@@ -665,7 +665,7 @@ bumpGeneration(Tree &tree,
 
 void
 AttributePostingListTest::
-removeOldGenerations(Tree &tree,
+reclaim_memory(Tree &tree,
                      ValueHandle &valueHandle,
                      PostingList &postings,
                      PostingListNodeAllocator &postingsAlloc)
diff --git a/searchlib/src/vespa/searchlib/attribute/attributevector.cpp b/searchlib/src/vespa/searchlib/attribute/attributevector.cpp
index 876830bb186..100470b5a5f 100644
--- a/searchlib/src/vespa/searchlib/attribute/attributevector.cpp
+++ b/searchlib/src/vespa/searchlib/attribute/attributevector.cpp
@@ -184,7 +184,7 @@ void
 AttributeVector::incGeneration()
 {
     // Freeze trees etc, to stop new readers from accessing currently held data
-    onGenerationChange(_genHandler.getNextGeneration());
+    before_inc_generation(_genHandler.getCurrentGeneration());
     _genHandler.incGeneration();
     // Remove old data on hold lists that can no longer be reached by readers
     removeAllOldGenerations();
@@ -237,8 +237,8 @@ AttributeVector::headerTypeOK(const vespalib::GenericHeader &header) const
         getConfig().collectionType().asString();
 }
 
-void AttributeVector::removeOldGenerations(generation_t firstUsed) { (void) firstUsed; }
-void AttributeVector::onGenerationChange(generation_t generation) { (void) generation; }
+void AttributeVector::reclaim_memory(generation_t oldest_used_gen) { (void) oldest_used_gen; }
+void AttributeVector::before_inc_generation(generation_t current_gen) { (void) current_gen; }
 const IEnumStore* AttributeVector::getEnumStoreBase() const { return nullptr; }
 IEnumStore* AttributeVector::getEnumStoreBase() { return nullptr; }
 const attribute::MultiValueMappingBase * AttributeVector::getMultiValueBase() const { return nullptr; }
@@ -410,7 +410,7 @@ bool AttributeVector::applyWeight(DocId, const FieldValue&, const AssignValueUpd
 void
 AttributeVector::removeAllOldGenerations() {
     _genHandler.update_oldest_used_generation();
-    removeOldGenerations(_genHandler.get_oldest_used_generation());
+    reclaim_memory(_genHandler.get_oldest_used_generation());
 }
 
 
diff --git a/searchlib/src/vespa/searchlib/attribute/attributevector.h b/searchlib/src/vespa/searchlib/attribute/attributevector.h
index 4d4cd8ac35f..6963814be0c 100644
--- a/searchlib/src/vespa/searchlib/attribute/attributevector.h
+++ b/searchlib/src/vespa/searchlib/attribute/attributevector.h
@@ -446,8 +446,8 @@ private:
     GenerationHandler::Guard takeGenerationGuard() { return _genHandler.takeGuard(); }
 
     /// Clean up [0, firstUsed>
-    virtual void removeOldGenerations(generation_t firstUsed);
-    virtual void onGenerationChange(generation_t generation);
+    virtual void reclaim_memory(generation_t oldest_used_gen);
+    virtual void before_inc_generation(generation_t current_gen);
     virtual void onUpdateStat() = 0;
     /**
      * Used to regulate access to critical resources. Apply the
diff --git a/searchlib/src/vespa/searchlib/attribute/flagattribute.cpp b/searchlib/src/vespa/searchlib/attribute/flagattribute.cpp
index df75b0ab4e5..f8cf742bdb2 100644
--- a/searchlib/src/vespa/searchlib/attribute/flagattribute.cpp
+++ b/searchlib/src/vespa/searchlib/attribute/flagattribute.cpp
@@ -229,10 +229,10 @@ FlagAttributeT<B>::resizeBitVectors(uint32_t neededSize)
 
 template <typename B>
 void
-FlagAttributeT<B>::removeOldGenerations(vespalib::GenerationHandler::generation_t firstUsed)
+FlagAttributeT<B>::reclaim_memory(vespalib::GenerationHandler::generation_t oldest_used_gen)
 {
-    B::removeOldGenerations(firstUsed);
-    _bitVectorHolder.reclaim(firstUsed);
+    B::reclaim_memory(oldest_used_gen);
+    _bitVectorHolder.reclaim(oldest_used_gen);
 }
 
 template class FlagAttributeT<FlagBaseImpl>;
diff --git a/searchlib/src/vespa/searchlib/attribute/flagattribute.h b/searchlib/src/vespa/searchlib/attribute/flagattribute.h
index 796c1493cc9..df75e7afa04 100644
--- a/searchlib/src/vespa/searchlib/attribute/flagattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/flagattribute.h
@@ -33,7 +33,7 @@ private:
     void ensureGuardBit();
     void clearGuardBit(DocId doc);
     void resizeBitVectors(uint32_t neededSize);
-    void removeOldGenerations(vespalib::GenerationHandler::generation_t firstUsed) override;
+    void reclaim_memory(vespalib::GenerationHandler::generation_t oldest_used_gen) override;
     uint32_t getOffset(int8_t value) const { return value + 128; }
 
     using AtomicBitVectorPtr = vespalib::datastore::AtomicValueWrapper<BitVector *>;
diff --git a/searchlib/src/vespa/searchlib/attribute/multienumattribute.h b/searchlib/src/vespa/searchlib/attribute/multienumattribute.h
index ee8f3181fd9..a073060afc5 100644
--- a/searchlib/src/vespa/searchlib/attribute/multienumattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/multienumattribute.h
@@ -63,8 +63,8 @@ public:
     void onCommit() override;
     void onUpdateStat() override;
 
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
 
     //-----------------------------------------------------------------------------------------------------------------
     // Attribute read API
diff --git a/searchlib/src/vespa/searchlib/attribute/multienumattribute.hpp b/searchlib/src/vespa/searchlib/attribute/multienumattribute.hpp
index ad827d0fd85..4dad82073e0 100644
--- a/searchlib/src/vespa/searchlib/attribute/multienumattribute.hpp
+++ b/searchlib/src/vespa/searchlib/attribute/multienumattribute.hpp
@@ -194,15 +194,15 @@ MultiValueEnumAttribute<B, M>::onUpdateStat()
 
 template <typename B, typename M>
 void
-MultiValueEnumAttribute<B, M>::removeOldGenerations(generation_t firstUsed)
+MultiValueEnumAttribute<B, M>::reclaim_memory(generation_t oldest_used_gen)
 {
-    this->_enumStore.reclaim_memory(firstUsed);
-    this->_mvMapping.reclaim_memory(firstUsed);
+    this->_enumStore.reclaim_memory(oldest_used_gen);
+    this->_mvMapping.reclaim_memory(oldest_used_gen);
 }
 
 template <typename B, typename M>
 void
-MultiValueEnumAttribute<B, M>::onGenerationChange(generation_t generation)
+MultiValueEnumAttribute<B, M>::before_inc_generation(generation_t current_gen)
 {
     /*
      * Freeze tree before generation is increased in attribute vector
@@ -211,8 +211,8 @@ MultiValueEnumAttribute<B, M>::onGenerationChange(generation_t generation)
      * sufficiently new frozen tree.
      */
     freezeEnumDictionary();
-    this->_mvMapping.assign_generation(generation - 1);
-    this->_enumStore.assign_generation(generation - 1);
+    this->_mvMapping.assign_generation(current_gen);
+    this->_enumStore.assign_generation(current_gen);
 }
 
 template <typename B, typename M>
diff --git a/searchlib/src/vespa/searchlib/attribute/multinumericattribute.h b/searchlib/src/vespa/searchlib/attribute/multinumericattribute.h
index 0a29b4af48d..ed78f7776f1 100644
--- a/searchlib/src/vespa/searchlib/attribute/multinumericattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/multinumericattribute.h
@@ -60,9 +60,9 @@ public:
     uint32_t getValueCount(DocId doc) const override;
     void onCommit() override;
     void onUpdateStat() override;
-    void removeOldGenerations(generation_t firstUsed) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
 
-    void onGenerationChange(generation_t generation) override;
+    void before_inc_generation(generation_t current_gen) override;
     bool onLoad(vespalib::Executor *executor) override;
     virtual bool onLoadEnumerated(ReaderBase &attrReader);
 
diff --git a/searchlib/src/vespa/searchlib/attribute/multinumericattribute.hpp b/searchlib/src/vespa/searchlib/attribute/multinumericattribute.hpp
index 2405841f331..b746fa5d555 100644
--- a/searchlib/src/vespa/searchlib/attribute/multinumericattribute.hpp
+++ b/searchlib/src/vespa/searchlib/attribute/multinumericattribute.hpp
@@ -96,16 +96,16 @@ void MultiValueNumericAttribute<B, M>::setNewValues(DocId doc, const std::vector
 }
 
 template <typename B, typename M>
-void MultiValueNumericAttribute<B, M>::removeOldGenerations(generation_t firstUsed)
+void MultiValueNumericAttribute<B, M>::reclaim_memory(generation_t oldest_used_gen)
 {
-    this->_mvMapping.reclaim_memory(firstUsed);
+    this->_mvMapping.reclaim_memory(oldest_used_gen);
 }
 
 
 template <typename B, typename M>
-void MultiValueNumericAttribute<B, M>::onGenerationChange(generation_t generation)
+void MultiValueNumericAttribute<B, M>::before_inc_generation(generation_t current_gen)
 {
-    this->_mvMapping.assign_generation(generation - 1);
+    this->_mvMapping.assign_generation(current_gen);
 }
 
 template <typename B, typename M>
diff --git a/searchlib/src/vespa/searchlib/attribute/multinumericpostattribute.h b/searchlib/src/vespa/searchlib/attribute/multinumericpostattribute.h
index 4bd8ad6e99f..a22a6241ab2 100644
--- a/searchlib/src/vespa/searchlib/attribute/multinumericpostattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/multinumericpostattribute.h
@@ -80,8 +80,8 @@ public:
     MultiValueNumericPostingAttribute(const vespalib::string & name, const AttributeVector::Config & cfg);
     ~MultiValueNumericPostingAttribute();
 
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
 
     std::unique_ptr<attribute::SearchContext>
     getSearch(QueryTermSimpleUP term, const attribute::SearchContextParams & params) const override;
diff --git a/searchlib/src/vespa/searchlib/attribute/multinumericpostattribute.hpp b/searchlib/src/vespa/searchlib/attribute/multinumericpostattribute.hpp
index 70a438f1551..deee72dcf39 100644
--- a/searchlib/src/vespa/searchlib/attribute/multinumericpostattribute.hpp
+++ b/searchlib/src/vespa/searchlib/attribute/multinumericpostattribute.hpp
@@ -56,19 +56,19 @@ MultiValueNumericPostingAttribute<B, M>::~MultiValueNumericPostingAttribute()
 
 template <typename B, typename M>
 void
-MultiValueNumericPostingAttribute<B, M>::removeOldGenerations(generation_t firstUsed)
+MultiValueNumericPostingAttribute<B, M>::reclaim_memory(generation_t oldest_used_gen)
 {
-    MultiValueNumericEnumAttribute<B, M>::removeOldGenerations(firstUsed);
-    _postingList.reclaim_memory(firstUsed);
+    MultiValueNumericEnumAttribute<B, M>::reclaim_memory(oldest_used_gen);
+    _postingList.reclaim_memory(oldest_used_gen);
 }
 
 template <typename B, typename M>
 void
-MultiValueNumericPostingAttribute<B, M>::onGenerationChange(generation_t generation)
+MultiValueNumericPostingAttribute<B, M>::before_inc_generation(generation_t current_gen)
 {
     _postingList.freeze();
-    MultiValueNumericEnumAttribute<B, M>::onGenerationChange(generation);
-    _postingList.assign_generation(generation - 1);
+    MultiValueNumericEnumAttribute<B, M>::before_inc_generation(current_gen);
+    _postingList.assign_generation(current_gen);
 }
 
 template <typename B, typename M>
diff --git a/searchlib/src/vespa/searchlib/attribute/multistringpostattribute.h b/searchlib/src/vespa/searchlib/attribute/multistringpostattribute.h
index 4deb71e9759..2e355a9aed2 100644
--- a/searchlib/src/vespa/searchlib/attribute/multistringpostattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/multistringpostattribute.h
@@ -77,8 +77,8 @@ public:
     MultiValueStringPostingAttributeT(const vespalib::string & name);
     ~MultiValueStringPostingAttributeT();
 
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
 
     std::unique_ptr<attribute::SearchContext>
     getSearch(QueryTermSimpleUP term, const attribute::SearchContextParams & params) const override;
diff --git a/searchlib/src/vespa/searchlib/attribute/multistringpostattribute.hpp b/searchlib/src/vespa/searchlib/attribute/multistringpostattribute.hpp
index 9bc2c31b163..cfd00f84636 100644
--- a/searchlib/src/vespa/searchlib/attribute/multistringpostattribute.hpp
+++ b/searchlib/src/vespa/searchlib/attribute/multistringpostattribute.hpp
@@ -75,19 +75,19 @@ MultiValueStringPostingAttributeT<B, T>::mergeMemoryStats(vespalib::MemoryUsage
 
 template <typename B, typename T>
 void
-MultiValueStringPostingAttributeT<B, T>::removeOldGenerations(generation_t firstUsed)
+MultiValueStringPostingAttributeT<B, T>::reclaim_memory(generation_t oldest_used_gen)
 {
-    MultiValueStringAttributeT<B, T>::removeOldGenerations(firstUsed);
-    _postingList.reclaim_memory(firstUsed);
+    MultiValueStringAttributeT<B, T>::reclaim_memory(oldest_used_gen);
+    _postingList.reclaim_memory(oldest_used_gen);
 }
 
 template <typename B, typename T>
 void
-MultiValueStringPostingAttributeT<B, T>::onGenerationChange(generation_t generation)
+MultiValueStringPostingAttributeT<B, T>::before_inc_generation(generation_t current_gen)
 {
     _postingList.freeze();
-    MultiValueStringAttributeT<B, T>::onGenerationChange(generation);
-    _postingList.assign_generation(generation - 1);
+    MultiValueStringAttributeT<B, T>::before_inc_generation(current_gen);
+    _postingList.assign_generation(current_gen);
 }
 
 
diff --git a/searchlib/src/vespa/searchlib/attribute/predicate_attribute.cpp b/searchlib/src/vespa/searchlib/attribute/predicate_attribute.cpp
index 8593b013443..f34099de758 100644
--- a/searchlib/src/vespa/searchlib/attribute/predicate_attribute.cpp
+++ b/searchlib/src/vespa/searchlib/attribute/predicate_attribute.cpp
@@ -125,17 +125,17 @@ PredicateAttribute::onUpdateStat()
 }
 
 void
-PredicateAttribute::removeOldGenerations(generation_t firstUsed)
+PredicateAttribute::reclaim_memory(generation_t oldest_used_gen)
 {
-    getGenerationHolder().reclaim(firstUsed);
-    _index->reclaim_memory(firstUsed);
+    getGenerationHolder().reclaim(oldest_used_gen);
+    _index->reclaim_memory(oldest_used_gen);
 }
 
 void
-PredicateAttribute::onGenerationChange(generation_t generation)
+PredicateAttribute::before_inc_generation(generation_t current_gen)
 {
-    getGenerationHolder().assign_generation(generation - 1);
-    _index->assign_generation(generation - 1);
+    getGenerationHolder().assign_generation(current_gen);
+    _index->assign_generation(current_gen);
 }
 
 void
diff --git a/searchlib/src/vespa/searchlib/attribute/predicate_attribute.h b/searchlib/src/vespa/searchlib/attribute/predicate_attribute.h
index f5d789298a0..159e71e99e3 100644
--- a/searchlib/src/vespa/searchlib/attribute/predicate_attribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/predicate_attribute.h
@@ -48,8 +48,8 @@ public:
     void onSave(IAttributeSaveTarget & saveTarget) override;
     bool onLoad(vespalib::Executor *executor) override;
     void onCommit() override;
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
     void onUpdateStat() override;
     bool addDoc(DocId &doc_id) override;
     uint32_t clearDoc(DocId doc_id) override;
diff --git a/searchlib/src/vespa/searchlib/attribute/reference_attribute.cpp b/searchlib/src/vespa/searchlib/attribute/reference_attribute.cpp
index aa884e1e298..e620d3aca72 100644
--- a/searchlib/src/vespa/searchlib/attribute/reference_attribute.cpp
+++ b/searchlib/src/vespa/searchlib/attribute/reference_attribute.cpp
@@ -161,21 +161,21 @@ ReferenceAttribute::clearDoc(DocId doc)
 }
 
 void
-ReferenceAttribute::removeOldGenerations(generation_t firstUsed)
+ReferenceAttribute::reclaim_memory(generation_t oldest_used_gen)
 {
-    _referenceMappings.reclaim_memory(firstUsed);
-    _store.reclaim_memory(firstUsed);
-    getGenerationHolder().reclaim(firstUsed);
+    _referenceMappings.reclaim_memory(oldest_used_gen);
+    _store.reclaim_memory(oldest_used_gen);
+    getGenerationHolder().reclaim(oldest_used_gen);
 }
 
 void
-ReferenceAttribute::onGenerationChange(generation_t generation)
+ReferenceAttribute::before_inc_generation(generation_t current_gen)
 {
     _referenceMappings.freeze();
     _store.freeze();
-    _referenceMappings.assign_generation(generation - 1);
-    _store.assign_generation(generation - 1);
-    getGenerationHolder().assign_generation(generation - 1);
+    _referenceMappings.assign_generation(current_gen);
+    _store.assign_generation(current_gen);
+    getGenerationHolder().assign_generation(current_gen);
 }
 
 void
diff --git a/searchlib/src/vespa/searchlib/attribute/reference_attribute.h b/searchlib/src/vespa/searchlib/attribute/reference_attribute.h
index dc3e2ad729a..e0ae906eb23 100644
--- a/searchlib/src/vespa/searchlib/attribute/reference_attribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/reference_attribute.h
@@ -50,8 +50,8 @@ private:
     ReferenceMappings _referenceMappings;
 
     void onAddDocs(DocId docIdLimit) override;
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
     void onCommit() override;
     void onUpdateStat() override;
     std::unique_ptr<AttributeSaver> onInitSave(vespalib::stringref fileName) override;
diff --git a/searchlib/src/vespa/searchlib/attribute/singleboolattribute.cpp b/searchlib/src/vespa/searchlib/attribute/singleboolattribute.cpp
index 6e07a9e658e..ac05ab3b7c6 100644
--- a/searchlib/src/vespa/searchlib/attribute/singleboolattribute.cpp
+++ b/searchlib/src/vespa/searchlib/attribute/singleboolattribute.cpp
@@ -257,13 +257,13 @@ SingleBoolAttribute::getEstimatedSaveByteSize() const
 }
 
 void
-SingleBoolAttribute::removeOldGenerations(generation_t firstUsed) {
-    getGenerationHolder().reclaim(firstUsed);
+SingleBoolAttribute::reclaim_memory(generation_t oldest_used_gen) {
+    getGenerationHolder().reclaim(oldest_used_gen);
 }
 
 void
-SingleBoolAttribute::onGenerationChange(generation_t generation) {
-    getGenerationHolder().assign_generation(generation - 1);
+SingleBoolAttribute::before_inc_generation(generation_t current_gen) {
+    getGenerationHolder().assign_generation(current_gen);
 }
 
 }
diff --git a/searchlib/src/vespa/searchlib/attribute/singleboolattribute.h b/searchlib/src/vespa/searchlib/attribute/singleboolattribute.h
index 7868c228e77..a02d5c7d80d 100644
--- a/searchlib/src/vespa/searchlib/attribute/singleboolattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/singleboolattribute.h
@@ -28,8 +28,8 @@ public:
     void onSave(IAttributeSaveTarget &saveTarget) override;
     void clearDocs(DocId lidLow, DocId lidLimit, bool in_shrink_lid_space) override;
     void onShrinkLidSpace() override;
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
     uint64_t getEstimatedSaveByteSize() const override;
 
     std::unique_ptr<attribute::SearchContext>
diff --git a/searchlib/src/vespa/searchlib/attribute/singleenumattribute.h b/searchlib/src/vespa/searchlib/attribute/singleenumattribute.h
index 6e46c697fbc..dbf3e4e7c58 100644
--- a/searchlib/src/vespa/searchlib/attribute/singleenumattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/singleenumattribute.h
@@ -111,8 +111,8 @@ public:
     uint32_t getValueCount(DocId doc) const override;
     void onCommit() override;
     void onUpdateStat() override;
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
     EnumHandle getEnum(DocId doc) const override {
        return getE(doc);
     }
diff --git a/searchlib/src/vespa/searchlib/attribute/singleenumattribute.hpp b/searchlib/src/vespa/searchlib/attribute/singleenumattribute.hpp
index f0649224b89..dd400295b3d 100644
--- a/searchlib/src/vespa/searchlib/attribute/singleenumattribute.hpp
+++ b/searchlib/src/vespa/searchlib/attribute/singleenumattribute.hpp
@@ -264,15 +264,15 @@ SingleValueEnumAttribute<B>::load_enumerated_data(ReaderBase& attrReader,
 
 template <typename B>
 void
-SingleValueEnumAttribute<B>::removeOldGenerations(generation_t firstUsed)
+SingleValueEnumAttribute<B>::reclaim_memory(generation_t oldest_used_gen)
 {
-    this->_enumStore.reclaim_memory(firstUsed);
-    getGenerationHolder().reclaim(firstUsed);
+    this->_enumStore.reclaim_memory(oldest_used_gen);
+    getGenerationHolder().reclaim(oldest_used_gen);
 }
 
 template <typename B>
 void
-SingleValueEnumAttribute<B>::onGenerationChange(generation_t generation)
+SingleValueEnumAttribute<B>::before_inc_generation(generation_t current_gen)
 {
     /*
      * Freeze tree before generation is increased in attribute vector
@@ -281,8 +281,8 @@ SingleValueEnumAttribute<B>::onGenerationChange(generation_t generation)
      * sufficiently new frozen tree.
      */
     freezeEnumDictionary();
-    getGenerationHolder().assign_generation(generation - 1);
-    this->_enumStore.assign_generation(generation - 1);
+    getGenerationHolder().assign_generation(current_gen);
+    this->_enumStore.assign_generation(current_gen);
 }
 
 
diff --git a/searchlib/src/vespa/searchlib/attribute/singlenumericattribute.h b/searchlib/src/vespa/searchlib/attribute/singlenumericattribute.h
index fd2767eaee1..c6387323fea 100644
--- a/searchlib/src/vespa/searchlib/attribute/singlenumericattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/singlenumericattribute.h
@@ -55,8 +55,8 @@ public:
     void onCommit() override;
     void onAddDocs(DocId lidLimit) override;
     void onUpdateStat() override;
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
     bool addDoc(DocId & doc) override;
     bool onLoad(vespalib::Executor *executor) override;
 
diff --git a/searchlib/src/vespa/searchlib/attribute/singlenumericattribute.hpp b/searchlib/src/vespa/searchlib/attribute/singlenumericattribute.hpp
index bbacc10e79c..66af5fe4adc 100644
--- a/searchlib/src/vespa/searchlib/attribute/singlenumericattribute.hpp
+++ b/searchlib/src/vespa/searchlib/attribute/singlenumericattribute.hpp
@@ -95,16 +95,16 @@ SingleValueNumericAttribute<B>::addDoc(DocId & doc) {
 
 template <typename B>
 void
-SingleValueNumericAttribute<B>::removeOldGenerations(generation_t firstUsed)
+SingleValueNumericAttribute<B>::reclaim_memory(generation_t oldest_used_gen)
 {
-    getGenerationHolder().reclaim(firstUsed);
+    getGenerationHolder().reclaim(oldest_used_gen);
 }
 
 template <typename B>
 void
-SingleValueNumericAttribute<B>::onGenerationChange(generation_t generation)
+SingleValueNumericAttribute<B>::before_inc_generation(generation_t current_gen)
 {
-    getGenerationHolder().assign_generation(generation - 1);
+    getGenerationHolder().assign_generation(current_gen);
 }
 
 template <typename B>
diff --git a/searchlib/src/vespa/searchlib/attribute/singlenumericpostattribute.h b/searchlib/src/vespa/searchlib/attribute/singlenumericpostattribute.h
index 720fb211e1a..f2343c1a57c 100644
--- a/searchlib/src/vespa/searchlib/attribute/singlenumericpostattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/singlenumericpostattribute.h
@@ -69,8 +69,8 @@ public:
     SingleValueNumericPostingAttribute(const vespalib::string & name, const AttributeVector::Config & cfg);
     ~SingleValueNumericPostingAttribute();
 
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
 
     std::unique_ptr<attribute::SearchContext>
     getSearch(QueryTermSimpleUP term, const attribute::SearchContextParams & params) const override;
diff --git a/searchlib/src/vespa/searchlib/attribute/singlenumericpostattribute.hpp b/searchlib/src/vespa/searchlib/attribute/singlenumericpostattribute.hpp
index c5acc0c360a..1775774171d 100644
--- a/searchlib/src/vespa/searchlib/attribute/singlenumericpostattribute.hpp
+++ b/searchlib/src/vespa/searchlib/attribute/singlenumericpostattribute.hpp
@@ -127,19 +127,19 @@ SingleValueNumericPostingAttribute<B>::applyValueChanges(EnumStoreBatchUpdater&
 
 template <typename B>
 void
-SingleValueNumericPostingAttribute<B>::removeOldGenerations(generation_t firstUsed)
+SingleValueNumericPostingAttribute<B>::reclaim_memory(generation_t oldest_used_gen)
 {
-    SingleValueNumericEnumAttribute<B>::removeOldGenerations(firstUsed);
-    _postingList.reclaim_memory(firstUsed);
+    SingleValueNumericEnumAttribute<B>::reclaim_memory(oldest_used_gen);
+    _postingList.reclaim_memory(oldest_used_gen);
 }
 
 template <typename B>
 void
-SingleValueNumericPostingAttribute<B>::onGenerationChange(generation_t generation)
+SingleValueNumericPostingAttribute<B>::before_inc_generation(generation_t current_gen)
 {
     _postingList.freeze();
-    SingleValueNumericEnumAttribute<B>::onGenerationChange(generation);
-    _postingList.assign_generation(generation - 1);
+    SingleValueNumericEnumAttribute<B>::before_inc_generation(current_gen);
+    _postingList.assign_generation(current_gen);
 }
 
 template <typename B>
diff --git a/searchlib/src/vespa/searchlib/attribute/singlesmallnumericattribute.cpp b/searchlib/src/vespa/searchlib/attribute/singlesmallnumericattribute.cpp
index 02ab5798f9f..b2662a0928d 100644
--- a/searchlib/src/vespa/searchlib/attribute/singlesmallnumericattribute.cpp
+++ b/searchlib/src/vespa/searchlib/attribute/singlesmallnumericattribute.cpp
@@ -106,16 +106,16 @@ SingleValueSmallNumericAttribute::onUpdateStat()
 
 
 void
-SingleValueSmallNumericAttribute::removeOldGenerations(generation_t firstUsed)
+SingleValueSmallNumericAttribute::reclaim_memory(generation_t oldest_used_gen)
 {
-    getGenerationHolder().reclaim(firstUsed);
+    getGenerationHolder().reclaim(oldest_used_gen);
 }
 
 
 void
-SingleValueSmallNumericAttribute::onGenerationChange(generation_t generation)
+SingleValueSmallNumericAttribute::before_inc_generation(generation_t current_gen)
 {
-    getGenerationHolder().assign_generation(generation - 1);
+    getGenerationHolder().assign_generation(current_gen);
 }
 
 
diff --git a/searchlib/src/vespa/searchlib/attribute/singlesmallnumericattribute.h b/searchlib/src/vespa/searchlib/attribute/singlesmallnumericattribute.h
index 4bf120d7952..b2af8752fa4 100644
--- a/searchlib/src/vespa/searchlib/attribute/singlesmallnumericattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/singlesmallnumericattribute.h
@@ -72,8 +72,8 @@ public:
     void onCommit() override;
     void onAddDocs(DocId docIdLimit) override;
     void onUpdateStat() override;
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
     bool addDoc(DocId & doc) override;
     bool onLoad(vespalib::Executor *executor) override;
     void onSave(IAttributeSaveTarget &saveTarget) override;
diff --git a/searchlib/src/vespa/searchlib/attribute/singlestringpostattribute.h b/searchlib/src/vespa/searchlib/attribute/singlestringpostattribute.h
index 30549f3048a..358c95f65dc 100644
--- a/searchlib/src/vespa/searchlib/attribute/singlestringpostattribute.h
+++ b/searchlib/src/vespa/searchlib/attribute/singlestringpostattribute.h
@@ -71,8 +71,8 @@ public:
     SingleValueStringPostingAttributeT(const vespalib::string & name);
     ~SingleValueStringPostingAttributeT();
 
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
 
     std::unique_ptr<attribute::SearchContext>
     getSearch(QueryTermSimpleUP term, const attribute::SearchContextParams & params) const override;
diff --git a/searchlib/src/vespa/searchlib/attribute/singlestringpostattribute.hpp b/searchlib/src/vespa/searchlib/attribute/singlestringpostattribute.hpp
index 5e7b70b5080..eef72984e79 100644
--- a/searchlib/src/vespa/searchlib/attribute/singlestringpostattribute.hpp
+++ b/searchlib/src/vespa/searchlib/attribute/singlestringpostattribute.hpp
@@ -127,19 +127,19 @@ SingleValueStringPostingAttributeT<B>::applyValueChanges(EnumStoreBatchUpdater&
 
 template <typename B>
 void
-SingleValueStringPostingAttributeT<B>::removeOldGenerations(generation_t firstUsed)
+SingleValueStringPostingAttributeT<B>::reclaim_memory(generation_t oldest_used_gen)
 {
-    SingleValueStringAttributeT<B>::removeOldGenerations(firstUsed);
-    _postingList.reclaim_memory(firstUsed);
+    SingleValueStringAttributeT<B>::reclaim_memory(oldest_used_gen);
+    _postingList.reclaim_memory(oldest_used_gen);
 }
 
 template <typename B>
 void
-SingleValueStringPostingAttributeT<B>::onGenerationChange(generation_t generation)
+SingleValueStringPostingAttributeT<B>::before_inc_generation(generation_t current_gen)
 {
     _postingList.freeze();
-    SingleValueStringAttributeT<B>::onGenerationChange(generation);
-    _postingList.assign_generation(generation - 1);
+    SingleValueStringAttributeT<B>::before_inc_generation(current_gen);
+    _postingList.assign_generation(current_gen);
 }
 
 template <typename B>
diff --git a/searchlib/src/vespa/searchlib/docstore/logdatastore.cpp b/searchlib/src/vespa/searchlib/docstore/logdatastore.cpp
index cdf7e5f5ea8..0e7e492c954 100644
--- a/searchlib/src/vespa/searchlib/docstore/logdatastore.cpp
+++ b/searchlib/src/vespa/searchlib/docstore/logdatastore.cpp
@@ -110,7 +110,7 @@ LogDataStore::~LogDataStore()
     // Must be called before ending threads as there are sanity checks.
     _fileChunks.clear();
     _genHandler.update_oldest_used_generation();
-    _lidInfo.removeOldGenerations(_genHandler.get_oldest_used_generation());
+    _lidInfo.reclaim_memory(_genHandler.get_oldest_used_generation());
 }
 
 void
@@ -940,7 +940,7 @@ LogDataStore::setLid(const MonitorGuard &guard, uint32_t lid, const LidInfo &met
     (void) guard;
     if (lid < _lidInfo.size()) {
         _genHandler.update_oldest_used_generation();
-        _lidInfo.removeOldGenerations(_genHandler.get_oldest_used_generation());
+        _lidInfo.reclaim_memory(_genHandler.get_oldest_used_generation());
         const LidInfo prev = vespalib::atomic::load_ref_relaxed(_lidInfo[lid]);
         if (prev.valid()) {
             _fileChunks[prev.getFileId()]->remove(lid, prev.size());
@@ -959,7 +959,7 @@ LogDataStore::incGeneration()
     _lidInfo.setGeneration(_genHandler.getNextGeneration());
     _genHandler.incGeneration();
     _genHandler.update_oldest_used_generation();
-    _lidInfo.removeOldGenerations(_genHandler.get_oldest_used_generation());
+    _lidInfo.reclaim_memory(_genHandler.get_oldest_used_generation());
 }
 
 size_t
diff --git a/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.cpp b/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.cpp
index 6a47e0da5df..56b9473b6e6 100644
--- a/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.cpp
@@ -450,22 +450,20 @@ DenseTensorAttribute::onCommit()
 }
 
 void
-DenseTensorAttribute::onGenerationChange(generation_t next_gen)
+DenseTensorAttribute::before_inc_generation(generation_t current_gen)
 {
-    // TODO: Change onGenerationChange() to send current generation instead of next generation.
-    //       This applies for entire attribute vector code.
-    TensorAttribute::onGenerationChange(next_gen);
+    TensorAttribute::before_inc_generation(current_gen);
     if (_index) {
-        _index->assign_generation(next_gen - 1);
+        _index->assign_generation(current_gen);
     }
 }
 
 void
-DenseTensorAttribute::removeOldGenerations(generation_t first_used_gen)
+DenseTensorAttribute::reclaim_memory(generation_t oldest_used_gen)
 {
-    TensorAttribute::removeOldGenerations(first_used_gen);
+    TensorAttribute::reclaim_memory(oldest_used_gen);
     if (_index) {
-        _index->reclaim_memory(first_used_gen);
+        _index->reclaim_memory(oldest_used_gen);
     }
 }
 
diff --git a/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.h b/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.h
index b0991aa57aa..3aa52fe622a 100644
--- a/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.h
+++ b/searchlib/src/vespa/searchlib/tensor/dense_tensor_attribute.h
@@ -47,8 +47,8 @@ public:
     std::unique_ptr<AttributeSaver> onInitSave(vespalib::stringref fileName) override;
     uint32_t getVersion() const override;
     void onCommit() override;
-    void onGenerationChange(generation_t next_gen) override;
-    void removeOldGenerations(generation_t first_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
     void get_state(const vespalib::slime::Inserter& inserter) const override;
     void onShrinkLidSpace() override;
 
diff --git a/searchlib/src/vespa/searchlib/tensor/hnsw_index.cpp b/searchlib/src/vespa/searchlib/tensor/hnsw_index.cpp
index d505e939a34..10f06a1e1ec 100644
--- a/searchlib/src/vespa/searchlib/tensor/hnsw_index.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/hnsw_index.cpp
@@ -523,7 +523,7 @@ HnswIndex::assign_generation(generation_t current_gen)
 void
 HnswIndex::reclaim_memory(generation_t oldest_used_gen)
 {
-    _graph.node_refs.removeOldGenerations(oldest_used_gen);
+    _graph.node_refs.reclaim_memory(oldest_used_gen);
     _graph.nodes.reclaim_memory(oldest_used_gen);
     _graph.links.reclaim_memory(oldest_used_gen);
 }
diff --git a/searchlib/src/vespa/searchlib/tensor/tensor_attribute.cpp b/searchlib/src/vespa/searchlib/tensor/tensor_attribute.cpp
index 1d147c14cca..6130da6fcf9 100644
--- a/searchlib/src/vespa/searchlib/tensor/tensor_attribute.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/tensor_attribute.cpp
@@ -110,17 +110,17 @@ TensorAttribute::onUpdateStat()
 }
 
 void
-TensorAttribute::removeOldGenerations(generation_t firstUsed)
+TensorAttribute::reclaim_memory(generation_t oldest_used_gen)
 {
-    _tensorStore.reclaim_memory(firstUsed);
-    getGenerationHolder().reclaim(firstUsed);
+    _tensorStore.reclaim_memory(oldest_used_gen);
+    getGenerationHolder().reclaim(oldest_used_gen);
 }
 
 void
-TensorAttribute::onGenerationChange(generation_t generation)
+TensorAttribute::before_inc_generation(generation_t current_gen)
 {
-    getGenerationHolder().assign_generation(generation - 1);
-    _tensorStore.assign_generation(generation - 1);
+    getGenerationHolder().assign_generation(current_gen);
+    _tensorStore.assign_generation(current_gen);
 }
 
 bool
diff --git a/searchlib/src/vespa/searchlib/tensor/tensor_attribute.h b/searchlib/src/vespa/searchlib/tensor/tensor_attribute.h
index 7cfbb68eac7..b7bac35d1b7 100644
--- a/searchlib/src/vespa/searchlib/tensor/tensor_attribute.h
+++ b/searchlib/src/vespa/searchlib/tensor/tensor_attribute.h
@@ -48,8 +48,8 @@ public:
     uint32_t clearDoc(DocId docId) override;
     void onCommit() override;
     void onUpdateStat() override;
-    void removeOldGenerations(generation_t firstUsed) override;
-    void onGenerationChange(generation_t generation) override;
+    void reclaim_memory(generation_t oldest_used_gen) override;
+    void before_inc_generation(generation_t current_gen) override;
     bool addDoc(DocId &docId) override;
     std::unique_ptr<vespalib::eval::Value> getEmptyTensor() const override;
     vespalib::eval::TypedCells extract_cells_ref(uint32_t docid) const override;
diff --git a/vespalib/src/tests/btree/frozenbtree_test.cpp b/vespalib/src/tests/btree/frozenbtree_test.cpp
index 0bde2786a0b..3471d5dc3df 100644
--- a/vespalib/src/tests/btree/frozenbtree_test.cpp
+++ b/vespalib/src/tests/btree/frozenbtree_test.cpp
@@ -114,7 +114,7 @@ FrozenBTreeTest::freeTree(bool verbose)
         static_cast<uint64_t>(_intTree->getUsedMemory()),
         static_cast<uint64_t>(_intTree->getHeldMemory()));
     _intTree->dropFrozen();
-    _intTree->removeOldGenerations(_intTree->getGeneration() + 1);
+    _intTree->reclaim_memory(_intTree->getGeneration() + 1);
     LOG(info,
         "freeTree after unhold: %" PRIu64 " (%" PRIu64 " held)",
         static_cast<uint64_t>(_intTree->getUsedMemory()),
diff --git a/vespalib/src/tests/util/rcuvector/rcuvector_test.cpp b/vespalib/src/tests/util/rcuvector/rcuvector_test.cpp
index 48fc88ec86d..5d6ec3050da 100644
--- a/vespalib/src/tests/util/rcuvector/rcuvector_test.cpp
+++ b/vespalib/src/tests/util/rcuvector/rcuvector_test.cpp
@@ -140,7 +140,7 @@ TEST(RcuVectorTest, generation_handling)
 
     v.setGeneration(2);
     v.push_back(50);
-    v.removeOldGenerations(3);
+    v.reclaim_memory(3);
     EXPECT_EQ(0u, v.getMemoryUsage().allocatedBytesOnHold());
     v.push_back(60); // new array
     EXPECT_EQ(24u, v.getMemoryUsage().allocatedBytesOnHold());
@@ -184,7 +184,7 @@ TEST(RcuVectorTest, memory_usage)
     EXPECT_TRUE(assertUsage(MemoryUsage(6,6,0,2), v.getMemoryUsage()));
     v.push_back(4);
     EXPECT_TRUE(assertUsage(MemoryUsage(12,11,0,6), v.getMemoryUsage()));
-    v.removeOldGenerations(1);
+    v.reclaim_memory(1);
     EXPECT_TRUE(assertUsage(MemoryUsage(6,5,0,0), v.getMemoryUsage()));
 }
 
diff --git a/vespalib/src/vespa/vespalib/util/rcuvector.h b/vespalib/src/vespa/vespalib/util/rcuvector.h
index 5d084fe3815..b0929303692 100644
--- a/vespalib/src/vespa/vespalib/util/rcuvector.h
+++ b/vespalib/src/vespa/vespalib/util/rcuvector.h
@@ -182,7 +182,7 @@ public:
     /**
      * Remove all old data vectors where generation < firstUsed.
      **/
-    void removeOldGenerations(generation_t firstUsed);
+    void reclaim_memory(generation_t oldest_used_gen);
 
     MemoryUsage getMemoryUsage() const override;
 };
diff --git a/vespalib/src/vespa/vespalib/util/rcuvector.hpp b/vespalib/src/vespa/vespalib/util/rcuvector.hpp
index e551bb17db0..eadda8ac1e9 100644
--- a/vespalib/src/vespa/vespalib/util/rcuvector.hpp
+++ b/vespalib/src/vespa/vespalib/util/rcuvector.hpp
@@ -187,9 +187,9 @@ RcuVector<T>::~RcuVector()
 
 template <typename T>
 void
-RcuVector<T>::removeOldGenerations(generation_t firstUsed)
+RcuVector<T>::reclaim_memory(generation_t oldest_used_gen)
 {
-    _genHolderStore.reclaim(firstUsed);
+    _genHolderStore.reclaim(oldest_used_gen);
 }
 
 template <typename T>