Merge pull request #28334 from vespa-engine/geirst/simplify-threading-service

Simplify IThreadingService as there only is one field writer executor.

15 files changed, 38 insertions, 116 deletions

diff --git a/searchcore/src/tests/proton/documentdb/configurer/configurer_test.cpp b/searchcore/src/tests/proton/documentdb/configurer/configurer_test.cpp
index 4af98801e92..28ec0482074 100644
--- a/searchcore/src/tests/proton/documentdb/configurer/configurer_test.cpp
+++ b/searchcore/src/tests/proton/documentdb/configurer/configurer_test.cpp
@@ -218,7 +218,7 @@ Fixture::initViewSet(ViewSet &views)
                                               TuneFileIndexManager(), TuneFileAttributes(), views._fileHeaderContext);
     auto attrMgr = make_shared<AttributeManager>(BASE_DIR, "test.subdb", TuneFileAttributes(),
                                                  views._fileHeaderContext, std::make_shared<search::attribute::Interlock>(),
-                                                 views._service.write().attributeFieldWriter(), views._service.write().shared(), views._hwInfo);
+                                                 views._service.write().field_writer(), views._service.write().shared(), views._hwInfo);
     auto summaryMgr = make_shared<SummaryManager>
             (_summaryExecutor, search::LogDocumentStore::Config(), search::GrowStrategy(), BASE_DIR,
              TuneFileSummary(), views._fileHeaderContext,views._noTlSyncer, search::IBucketizer::SP());
@@ -318,7 +318,7 @@ struct MyFastAccessFeedView
         StoreOnlyFeedView::PersistentParams params(1, 1, DocTypeName(DOC_TYPE), 0, SubDbType::NOTREADY);
         auto mgr = make_shared<AttributeManager>(BASE_DIR, "test.subdb", TuneFileAttributes(),
                                                  _fileHeaderContext, std::make_shared<search::attribute::Interlock>(),
-                                                 _writeService.attributeFieldWriter(), _writeService.shared(), _hwInfo);
+                                                 _writeService.field_writer(), _writeService.shared(), _hwInfo);
         auto writer = std::make_shared<AttributeWriter>(mgr);
         FastAccessFeedView::Context fastUpdateCtx(writer, _docIdLimit);
         _feedView.set(std::make_shared<FastAccessFeedView>(std::move(storeOnlyCtx), params, fastUpdateCtx));
diff --git a/searchcore/src/tests/proton/documentdb/executor_threading_service/executor_threading_service_test.cpp b/searchcore/src/tests/proton/documentdb/executor_threading_service/executor_threading_service_test.cpp
index bc02f460b4e..9bba8c12ee7 100644
--- a/searchcore/src/tests/proton/documentdb/executor_threading_service/executor_threading_service_test.cpp
+++ b/searchcore/src/tests/proton/documentdb/executor_threading_service/executor_threading_service_test.cpp
@@ -34,15 +34,6 @@ public:
                                                              ThreadingServiceConfig::make()))
     {
     }
-    SequencedTaskExecutor* index_inverter() {
-        return to_concrete_type(service->indexFieldInverter());
-    }
-    SequencedTaskExecutor* index_writer() {
-        return to_concrete_type(service->indexFieldWriter());
-    }
-    SequencedTaskExecutor* attribute_writer() {
-        return to_concrete_type(service->attributeFieldWriter());
-    }
     SequencedTaskExecutor* field_writer() {
         return to_concrete_type(*field_writer_executor);
     }
@@ -57,9 +48,7 @@ assert_executor(SequencedTaskExecutor* exec, uint32_t exp_executors, uint32_t ex
 
 TEST_F(ExecutorThreadingServiceTest, shared_field_writer_specified_from_the_outside)
 {
-    EXPECT_EQ(field_writer(), index_inverter());
-    EXPECT_EQ(field_writer(), index_writer());
-    EXPECT_EQ(field_writer(), attribute_writer());
+    EXPECT_EQ(field_writer(), &service->field_writer());
     assert_executor(field_writer(), 3, 200);
 }
 
@@ -69,9 +58,7 @@ TEST_F(ExecutorThreadingServiceTest, tasks_limits_can_be_updated)
     EXPECT_EQ(5, service->master_task_limit());
     EXPECT_EQ(7, service->index().getTaskLimit());
     EXPECT_EQ(11, service->summary().getTaskLimit());
-    EXPECT_EQ(7, index_inverter()->first_executor()->getTaskLimit());
-    EXPECT_EQ(7, index_writer()->first_executor()->getTaskLimit());
-    EXPECT_EQ(7, attribute_writer()->first_executor()->getTaskLimit());
+    EXPECT_EQ(7, field_writer()->first_executor()->getTaskLimit());
 }
 
 GTEST_MAIN_RUN_ALL_TESTS()
diff --git a/searchcore/src/tests/proton/index/fusionrunner_test.cpp b/searchcore/src/tests/proton/index/fusionrunner_test.cpp
index 9052d024871..e57b1b6a61d 100644
--- a/searchcore/src/tests/proton/index/fusionrunner_test.cpp
+++ b/searchcore/src/tests/proton/index/fusionrunner_test.cpp
@@ -192,8 +192,8 @@ void Test::createIndex(const string &dir, uint32_t id, bool fusion) {
     DocBuilder doc_builder(add_fields);
     auto schema = SchemaBuilder(doc_builder).add_all_indexes().build();
     MemoryIndex memory_index(schema, MockFieldLengthInspector(),
-                             _service.write().indexFieldInverter(),
-                             _service.write().indexFieldWriter());
+                             _service.write().field_writer(),
+                             _service.write().field_writer());
     addDocument(doc_builder, memory_index, *_selector, id, id + 0, term);
     addDocument(doc_builder, memory_index, *_selector, id, id + 1, "bar");
     addDocument(doc_builder, memory_index, *_selector, id, id + 2, "baz");
diff --git a/searchcore/src/vespa/searchcore/proton/index/memoryindexwrapper.cpp b/searchcore/src/vespa/searchcore/proton/index/memoryindexwrapper.cpp
index 219283dce04..e4c47d1deae 100644
--- a/searchcore/src/vespa/searchcore/proton/index/memoryindexwrapper.cpp
+++ b/searchcore/src/vespa/searchcore/proton/index/memoryindexwrapper.cpp
@@ -23,8 +23,8 @@ MemoryIndexWrapper::MemoryIndexWrapper(const search::index::Schema& schema,
                                        const TuneFileIndexing& tuneFileIndexing,
                                        searchcorespi::index::IThreadingService& threadingService,
                                        search::SerialNum serialNum)
-    : _index(schema, inspector, threadingService.indexFieldInverter(),
-             threadingService.indexFieldWriter()),
+    : _index(schema, inspector, threadingService.field_writer(),
+             threadingService.field_writer()),
       _serialNum(serialNum),
       _fileHeaderContext(fileHeaderContext),
       _tuneFileIndexing(tuneFileIndexing)
diff --git a/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_metrics.cpp b/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_metrics.cpp
index 030dba4d826..43b38c8d812 100644
--- a/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_metrics.cpp
+++ b/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_metrics.cpp
@@ -24,9 +24,10 @@ ExecutorThreadingServiceMetrics::update(const ExecutorThreadingServiceStats &sta
     master.update(stats.getMasterExecutorStats());
     index.update(stats.getIndexExecutorStats());
     summary.update(stats.getSummaryExecutorStats());
-    indexFieldInverter.update(stats.getIndexFieldInverterExecutorStats());
-    indexFieldWriter.update(stats.getIndexFieldWriterExecutorStats());
-    attributeFieldWriter.update(stats.getAttributeFieldWriterExecutorStats());
+    vespalib::ExecutorStats empty_stats;
+    indexFieldInverter.update(empty_stats);
+    indexFieldWriter.update(empty_stats);
+    attributeFieldWriter.update(empty_stats);
 }
 
 }
diff --git a/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_stats.cpp b/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_stats.cpp
index 63644e5c7ab..9d22344eb2b 100644
--- a/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_stats.cpp
+++ b/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_stats.cpp
@@ -6,16 +6,10 @@ namespace proton {
 
 ExecutorThreadingServiceStats::ExecutorThreadingServiceStats(Stats masterExecutorStats,
                                                              Stats indexExecutorStats,
-                                                             Stats summaryExecutorStats,
-                                                             Stats indexFieldInverterExecutorStats,
-                                                             Stats indexFieldWriterExecutorStats,
-                                                             Stats attributeFieldWriterExecutorStats)
+                                                             Stats summaryExecutorStats)
     : _masterExecutorStats(masterExecutorStats),
       _indexExecutorStats(indexExecutorStats),
-      _summaryExecutorStats(summaryExecutorStats),
-      _indexFieldInverterExecutorStats(indexFieldInverterExecutorStats),
-      _indexFieldWriterExecutorStats(indexFieldWriterExecutorStats),
-      _attributeFieldWriterExecutorStats(attributeFieldWriterExecutorStats)
+      _summaryExecutorStats(summaryExecutorStats)
 {
 }
 
diff --git a/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_stats.h b/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_stats.h
index 8015ec83ae9..121ca6038b6 100644
--- a/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_stats.h
+++ b/searchcore/src/vespa/searchcore/proton/metrics/executor_threading_service_stats.h
@@ -16,24 +16,15 @@ private:
     Stats _masterExecutorStats;
     Stats _indexExecutorStats;
     Stats _summaryExecutorStats;
-    Stats _indexFieldInverterExecutorStats;
-    Stats _indexFieldWriterExecutorStats;
-    Stats _attributeFieldWriterExecutorStats;
 public:
     ExecutorThreadingServiceStats(Stats masterExecutorStats,
                                   Stats indexExecutorStats,
-                                  Stats summaryExecutorStats,
-                                  Stats indexFieldInverterExecutorStats,
-                                  Stats indexFieldWriterExecutorStats,
-                                  Stats attributeFieldWriterExecutorStats);
+                                  Stats summaryExecutorStats);
     ~ExecutorThreadingServiceStats();
 
     const Stats &getMasterExecutorStats() const { return _masterExecutorStats; }
     const Stats &getIndexExecutorStats() const { return _indexExecutorStats; }
     const Stats &getSummaryExecutorStats() const { return _summaryExecutorStats; }
-    const Stats &getIndexFieldInverterExecutorStats() const { return _indexFieldInverterExecutorStats; }
-    const Stats &getIndexFieldWriterExecutorStats() const { return _indexFieldWriterExecutorStats; }
-    const Stats &getAttributeFieldWriterExecutorStats() const { return _attributeFieldWriterExecutorStats; }
 };
 
 }
diff --git a/searchcore/src/vespa/searchcore/proton/server/documentdb.cpp b/searchcore/src/vespa/searchcore/proton/server/documentdb.cpp
index 3f28f75c521..b0d168fab03 100644
--- a/searchcore/src/vespa/searchcore/proton/server/documentdb.cpp
+++ b/searchcore/src/vespa/searchcore/proton/server/documentdb.cpp
@@ -413,7 +413,7 @@ DocumentDB::applySubDBConfig(const DocumentDBConfig &newConfigSnapshot,
     auto newDocType = newRepo->getDocumentType(_docTypeName.getName());
     assert(newDocType != nullptr);
     DocumentDBReferenceResolver resolver(*registry, *newDocType, newConfigSnapshot.getImportedFieldsConfig(), *oldDocType,
-                                         _refCount, _writeService.attributeFieldWriter(), _state.getAllowReconfig());
+                                         _refCount, _writeService.field_writer(), _state.getAllowReconfig());
     _subDBs.applyConfig(newConfigSnapshot, *_activeConfigSnapshot, serialNum, params, resolver, prepared_reconfig);
 }
 
@@ -535,7 +535,7 @@ DocumentDB::tearDownReferences()
     auto docType = repo->getDocumentType(_docTypeName.getName());
     assert(docType != nullptr);
     DocumentDBReferenceResolver resolver(*registry, *docType, activeConfig->getImportedFieldsConfig(), *docType,
-                                         _refCount, _writeService.attributeFieldWriter(), false);
+                                         _refCount, _writeService.field_writer(), false);
     _subDBs.tearDownReferences(resolver);
     registry->remove(_docTypeName.getName());
 }
diff --git a/searchcore/src/vespa/searchcore/proton/server/executor_threading_service_explorer.cpp b/searchcore/src/vespa/searchcore/proton/server/executor_threading_service_explorer.cpp
index 9dfebaa825d..9bd60af81ca 100644
--- a/searchcore/src/vespa/searchcore/proton/server/executor_threading_service_explorer.cpp
+++ b/searchcore/src/vespa/searchcore/proton/server/executor_threading_service_explorer.cpp
@@ -24,9 +24,7 @@ ExecutorThreadingServiceExplorer::get_state(const vespalib::slime::Inserter& ins
         convert_executor_to_slime(&_service.master(), object.setObject("master"));
         convert_executor_to_slime(&_service.index(), object.setObject("index"));
         convert_executor_to_slime(&_service.summary(), object.setObject("summary"));
-        convert_executor_to_slime(&_service.indexFieldInverter(), object.setObject("index_field_inverter"));
-        convert_executor_to_slime(&_service.indexFieldWriter(), object.setObject("index_field_writer"));
-        convert_executor_to_slime(&_service.attributeFieldWriter(), object.setObject("attribute_field_writer"));
+        convert_executor_to_slime(&_service.field_writer(), object.setObject("field_writer"));
     }
 }
 
diff --git a/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.cpp b/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.cpp
index 4798ebd8fbc..01fc0ff3600 100644
--- a/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.cpp
+++ b/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.cpp
@@ -65,9 +65,7 @@ ExecutorThreadingService::ExecutorThreadingService(vespalib::Executor & sharedEx
       _summaryExecutor(createExecutorWithOneThread(cfg, CpuUsage::wrap(summary_executor, CpuUsage::Category::WRITE))),
       _masterService(_masterExecutor),
       _indexService(*_indexExecutor),
-      _index_field_inverter(field_writer),
-      _index_field_writer(field_writer),
-      _attribute_field_writer(field_writer),
+      _field_writer(field_writer),
       _invokeRegistrations()
 {
     if (cfg.optimize() == vespalib::Executor::OptimizeFor::THROUGHPUT && invokerService) {
@@ -92,11 +90,11 @@ void
 ExecutorThreadingService::shutdown()
 {
     _masterExecutor.shutdown().sync();
-    _attribute_field_writer.sync_all();
+    _field_writer.sync_all();
     _summaryExecutor->shutdown().sync();
     _indexExecutor->shutdown().sync();
-    _index_field_inverter.sync_all();
-    _index_field_writer.sync_all();
+    _field_writer.sync_all();
+    _field_writer.sync_all();
 }
 
 void
@@ -107,10 +105,7 @@ ExecutorThreadingService::set_task_limits(uint32_t master_task_limit,
     _master_task_limit.store(master_task_limit, std::memory_order_release);
     _indexExecutor->setTaskLimit(field_task_limit);
     _summaryExecutor->setTaskLimit(summary_task_limit);
-    // TODO: Move this to a common place when the field writer is always shared.
-    _index_field_inverter.setTaskLimit(field_task_limit);
-    _index_field_writer.setTaskLimit(field_task_limit);
-    _attribute_field_writer.setTaskLimit(field_task_limit);
+    _field_writer.setTaskLimit(field_task_limit);
 }
 
 ExecutorThreadingServiceStats
@@ -119,26 +114,13 @@ ExecutorThreadingService::getStats()
     auto master_stats = _masterExecutor.getStats();
     auto index_stats = _indexExecutor->getStats();
     auto summary_stats = _summaryExecutor->getStats();
-    vespalib::ExecutorStats empty_stats;
-    // In this case the field writer stats are reported at a higher level.
-    return ExecutorThreadingServiceStats(master_stats, index_stats, summary_stats,
-                                         empty_stats, empty_stats, empty_stats);
+    return ExecutorThreadingServiceStats(master_stats, index_stats, summary_stats);
 }
 
 vespalib::ISequencedTaskExecutor &
-ExecutorThreadingService::indexFieldInverter() {
-    return _index_field_inverter;
+ExecutorThreadingService::field_writer() {
+    return _field_writer;
 }
 
-vespalib::ISequencedTaskExecutor &
-ExecutorThreadingService::indexFieldWriter() {
-    return _index_field_writer;
 }
 
-vespalib::ISequencedTaskExecutor &
-ExecutorThreadingService::attributeFieldWriter() {
-    return _attribute_field_writer;
-}
-
-} // namespace proton
-
diff --git a/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.h b/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.h
index 9da4348c619..ad630c6b1e7 100644
--- a/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.h
+++ b/searchcore/src/vespa/searchcore/proton/server/executorthreadingservice.h
@@ -29,9 +29,7 @@ private:
     std::unique_ptr<vespalib::SyncableThreadExecutor>    _summaryExecutor;
     SyncableExecutorThreadService                        _masterService;
     ExecutorThreadService                                _indexService;
-    vespalib::ISequencedTaskExecutor&                    _index_field_inverter;
-    vespalib::ISequencedTaskExecutor&                    _index_field_writer;
-    vespalib::ISequencedTaskExecutor&                    _attribute_field_writer;
+    vespalib::ISequencedTaskExecutor&                    _field_writer;
     std::vector<Registration>                            _invokeRegistrations;
 
 public:
@@ -77,9 +75,7 @@ public:
         return _sharedExecutor;
     }
 
-    vespalib::ISequencedTaskExecutor &indexFieldInverter() override;
-    vespalib::ISequencedTaskExecutor &indexFieldWriter() override;
-    vespalib::ISequencedTaskExecutor &attributeFieldWriter() override;
+    vespalib::ISequencedTaskExecutor &field_writer() override;
     FNET_Transport &transport() override { return _transport; }
     const vespalib::Clock &clock() const override { return _clock; }
     ExecutorThreadingServiceStats getStats();
diff --git a/searchcore/src/vespa/searchcore/proton/server/fast_access_doc_subdb.cpp b/searchcore/src/vespa/searchcore/proton/server/fast_access_doc_subdb.cpp
index 8a3de22656b..47dd8c03706 100644
--- a/searchcore/src/vespa/searchcore/proton/server/fast_access_doc_subdb.cpp
+++ b/searchcore/src/vespa/searchcore/proton/server/fast_access_doc_subdb.cpp
@@ -70,7 +70,7 @@ FastAccessDocSubDB::createAttributeManagerInitializer(const DocumentDBConfig &co
                                                configSnapshot.getTuneFileDocumentDBSP()->_attr,
                                                _fileHeaderContext,
                                                _attribute_interlock,
-                                               _writeService.attributeFieldWriter(),
+                                               _writeService.field_writer(),
                                                _writeService.shared(),
                                                attrFactory,
                                                _hwInfo);
diff --git a/searchcore/src/vespa/searchcore/proton/test/threading_service_observer.cpp b/searchcore/src/vespa/searchcore/proton/test/threading_service_observer.cpp
index 4112564632a..2790c0962b4 100644
--- a/searchcore/src/vespa/searchcore/proton/test/threading_service_observer.cpp
+++ b/searchcore/src/vespa/searchcore/proton/test/threading_service_observer.cpp
@@ -10,9 +10,7 @@ ThreadingServiceObserver::ThreadingServiceObserver(searchcorespi::index::IThread
       _index(service.index()),
       _summary(service.summary()),
       _shared(service.shared()),
-      _indexFieldInverter(_service.indexFieldInverter()),
-      _indexFieldWriter(_service.indexFieldWriter()),
-      _attributeFieldWriter(_service.attributeFieldWriter())
+      _field_writer(_service.field_writer())
 {
 }
 
diff --git a/searchcore/src/vespa/searchcore/proton/test/threading_service_observer.h b/searchcore/src/vespa/searchcore/proton/test/threading_service_observer.h
index 16b466a2275..56b5fea293c 100644
--- a/searchcore/src/vespa/searchcore/proton/test/threading_service_observer.h
+++ b/searchcore/src/vespa/searchcore/proton/test/threading_service_observer.h
@@ -16,9 +16,7 @@ private:
     ThreadServiceObserver          _index;
     ThreadExecutorObserver         _summary;
     vespalib::Executor           & _shared;
-    vespalib::SequencedTaskExecutorObserver _indexFieldInverter;
-    vespalib::SequencedTaskExecutorObserver _indexFieldWriter;
-    vespalib::SequencedTaskExecutorObserver _attributeFieldWriter;
+    vespalib::SequencedTaskExecutorObserver _field_writer;
 
 public:
     ThreadingServiceObserver(searchcorespi::index::IThreadingService &service);
@@ -51,17 +49,9 @@ public:
     }
     FNET_Transport & transport() override { return _service.transport(); }
     const vespalib::Clock & clock() const override { return _service.clock(); }
-    vespalib::ISequencedTaskExecutor &indexFieldInverter() override {
-        return _indexFieldInverter;
+    vespalib::ISequencedTaskExecutor &field_writer() override {
+        return _field_writer;
     }
-    vespalib::ISequencedTaskExecutor &indexFieldWriter() override {
-        return _indexFieldWriter;
-    }
-
-    vespalib::ISequencedTaskExecutor &attributeFieldWriter() override {
-        return _attributeFieldWriter;
-    }
-
 };
 
 }
diff --git a/searchcore/src/vespa/searchcorespi/index/ithreadingservice.h b/searchcore/src/vespa/searchcorespi/index/ithreadingservice.h
index c325d5ded11..4fce6f85a2b 100644
--- a/searchcore/src/vespa/searchcorespi/index/ithreadingservice.h
+++ b/searchcore/src/vespa/searchcorespi/index/ithreadingservice.h
@@ -20,19 +20,19 @@ namespace searchcorespi::index {
  *
  *  2. The "index" write thread used for doing changes to the memory
  *     index, either directly (for data not bound to a field) or via
- *     index field inverter executor or index field writer executor.
+ *     field writer executor (index field inverter / index field writer).
  *
  *  3. The "summary" thread is used for doing changes to the document store.
  *
- *  4. The "index field inverter" executor is used to populate field
+ *  4. The field writer executor ("index field inverter") is used to populate field
  *     inverters with data from document fields.  Scheduled tasks for
  *     the same field are executed in sequence.
  *
- *  5. The "index field writer" executor is used to sort data in field
+ *  5. The field writer executor ("index field writer") is used to sort data in field
  *     inverters before pushing the data to the memory field indexes.
  *     Scheduled tasks for the same field are executed in sequence.
  *
- *  6. The "attribute field writer" executor is used to write data to attribute vectors.
+ *  6. The field writer executor ("attribute field writer") is used to write data to attribute vectors.
  *     Each attribute is always handled by the same thread,
  *     and scheduled tasks for the same attribute are executed in sequence.
  *
@@ -47,19 +47,6 @@ namespace searchcorespi::index {
  * task to the index field inverter executor and the index field
  * writer executor.
  *
- * The index field inverter executor and index field writer executor
- * are separate to allow for double buffering, i.e. populate one set
- * of field inverters using the index field inverter executor while
- * another set of field inverters are handled by the index field
- * writer executor.
- *
- * We might decide to allow index field inverter tasks to schedule
- * tasks to the index field writer executor, so draining logic needs
- * to sync index field inverter executor before syncing index field
- * writer executor.
- *
- * TODO: * indexFieldInverter and indexFieldWriter can be collapsed to one. Both need sequencing,
- *         but they sequence on different things so efficiency will be the same and just depends on #threads
  */
 struct IThreadingService
 {
@@ -80,9 +67,7 @@ struct IThreadingService
     virtual vespalib::Executor &shared() = 0;
     virtual FNET_Transport &transport() = 0;
     virtual const vespalib::Clock &clock() const = 0;
-    virtual vespalib::ISequencedTaskExecutor &indexFieldInverter() = 0;
-    virtual vespalib::ISequencedTaskExecutor &indexFieldWriter() = 0;
-    virtual vespalib::ISequencedTaskExecutor &attributeFieldWriter() = 0;
+    virtual vespalib::ISequencedTaskExecutor &field_writer() = 0;
 };
 
 }