create engine-specific transaction context data

arangod/CMakeLists.txt

@@ -250,6 +250,7 @@ SET(ARANGOD_SOURCES
   MMFiles/MMFilesSkiplistIndex.cpp
   MMFiles/MMFilesSynchronizerThread.cpp
   MMFiles/MMFilesTransactionCollection.cpp
+  MMFiles/MMFilesTransactionContextData.cpp
   MMFiles/MMFilesTransactionState.cpp
   MMFiles/MMFilesWalLogfile.cpp
   MMFiles/MMFilesWalRecoverState.cpp

arangod/MMFiles/MMFilesEngine.cpp

@@ -31,10 +31,6 @@
 #include "Basics/WriteLocker.h"
 #include "Basics/encoding.h"
 #include "Basics/files.h"
-#include "Random/RandomGenerator.h"
-#include "RestServer/DatabaseFeature.h"
-#include "RestServer/DatabasePathFeature.h"
-#include "StorageEngine/EngineSelectorFeature.h"
 #include "MMFiles/MMFilesAqlFunctions.h"
 #include "MMFiles/MMFilesCleanupThread.h"
 #include "MMFiles/MMFilesCompactorThread.h"
@@ -45,7 +41,12 @@
 #include "MMFiles/MMFilesPersistentIndex.h"
 #include "MMFiles/MMFilesPersistentIndexFeature.h"
 #include "MMFiles/MMFilesTransactionCollection.h"
+#include "MMFiles/MMFilesTransactionContextData.h"
 #include "MMFiles/MMFilesTransactionState.h"
+#include "Random/RandomGenerator.h"
+#include "RestServer/DatabaseFeature.h"
+#include "RestServer/DatabasePathFeature.h"
+#include "StorageEngine/EngineSelectorFeature.h"
 #include "VocBase/LogicalCollection.h"
 #include "VocBase/ticks.h"
 #include "VocBase/vocbase.h"
@@ -224,6 +225,10 @@ void MMFilesEngine::stop() {
   logfileManager->waitForCollector();
 }
  
+transaction::ContextData* MMFilesEngine::createTransactionContextData() {
+  return new MMFilesTransactionContextData;
+}
+
 TransactionState* MMFilesEngine::createTransactionState(TRI_vocbase_t* vocbase) {
   return new MMFilesTransactionState(vocbase);
 }

arangod/MMFiles/MMFilesEngine.h

@@ -40,6 +40,10 @@ class MMFilesCompactorThread;
 class TransactionCollection;
 class TransactionState;
 
+namespace transaction {
+class ContextData;
+}
+
 /// @brief collection file structure
 struct MMFilesEngineCollectionFiles {
   std::vector<std::string> journals;
@@ -75,6 +79,7 @@ class MMFilesEngine final : public StorageEngine {
   // flush wal wait for collector
   void stop() override;
 
+  transaction::ContextData* createTransactionContextData() override;
   TransactionState* createTransactionState(TRI_vocbase_t*) override;
   TransactionCollection* createTransactionCollection(TransactionState* state, TRI_voc_cid_t cid, AccessMode::Type accessType, int nestingLevel) override;
 

arangod/MMFiles/MMFilesTransactionContextData.cpp

@@ -0,0 +1,75 @@
+////////////////////////////////////////////////////////////////////////////////
+/// DISCLAIMER
+///
+/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
+/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is ArangoDB GmbH, Cologne, Germany
+///
+/// @author Jan Steemann
+////////////////////////////////////////////////////////////////////////////////
+
+#include "MMFilesTransactionContextData.h"
+#include "MMFiles/MMFilesCollection.h"
+#include "MMFiles/MMFilesDitch.h"
+#include "VocBase/LogicalCollection.h"
+
+using namespace arangodb;
+
+MMFilesTransactionContextData::MMFilesTransactionContextData() {}
+
+MMFilesTransactionContextData::~MMFilesTransactionContextData() {
+  for (auto& it : _ditches) {
+    // we're done with this ditch
+    auto& ditch = it.second;
+    ditch->ditches()->freeMMFilesDocumentDitch(ditch, true /* fromTransaction */);
+    // If some external entity is still using the ditch, it is kept!
+  }
+}
+
+/// @brief pin data for the collection
+void MMFilesTransactionContextData::pinData(LogicalCollection* collection) {
+  TRI_voc_cid_t cid = collection->cid();
+
+  auto it = _ditches.find(cid);
+
+  if (it != _ditches.end()) {
+    // tell everyone else this ditch is still in use,
+    // at least until the transaction is over
+    TRI_ASSERT((*it).second->usedByTransaction());
+    // ditch already exists
+    return;
+  }
+
+  // this method will not throw, but may return a nullptr
+  auto ditch = arangodb::MMFilesCollection::toMMFilesCollection(collection)->ditches()->createMMFilesDocumentDitch(true, __FILE__, __LINE__);
+
+  if (ditch == nullptr) {
+    THROW_ARANGO_EXCEPTION(TRI_ERROR_OUT_OF_MEMORY);
+  }
+
+  try {
+    _ditches.emplace(cid, ditch);
+  }
+  catch (...) {
+    ditch->ditches()->freeMMFilesDocumentDitch(ditch, true);
+    throw;
+  }
+}
+
+/// @brief whether or not the data for the collection is pinned
+bool MMFilesTransactionContextData::isPinned(TRI_voc_cid_t cid) const {
+  return (_ditches.find(cid) != _ditches.end());
+}

arangod/MMFiles/MMFilesTransactionContextData.h

@@ -0,0 +1,53 @@
+////////////////////////////////////////////////////////////////////////////////
+/// DISCLAIMER
+///
+/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
+/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is ArangoDB GmbH, Cologne, Germany
+///
+/// @author Jan Steemann
+////////////////////////////////////////////////////////////////////////////////
+
+#ifndef ARANGOD_MMFILES_TRANSACTION_CONTEXT_DATA_H
+#define ARANGOD_MMFILES_TRANSACTION_CONTEXT_DATA_H 1
+
+#include "Basics/Common.h"
+#include "Transaction/ContextData.h"
+#include "VocBase/voc-types.h"
+                                
+namespace arangodb {
+class LogicalCollection;
+class MMFilesDocumentDitch;
+
+/// @brief transaction type
+class MMFilesTransactionContextData final : public transaction::ContextData {
+ public:
+  MMFilesTransactionContextData();
+  ~MMFilesTransactionContextData();
+  
+  /// @brief pin data for the collection
+  void pinData(arangodb::LogicalCollection*) override;
+
+  /// @brief whether or not the data for the collection is pinned
+  bool isPinned(TRI_voc_cid_t) const override;
+  
+ private:
+  std::unordered_map<TRI_voc_cid_t, MMFilesDocumentDitch*> _ditches;
+};
+
+}
+
+#endif

arangod/MMFiles/MMFilesTransactionState.h

@@ -45,7 +45,6 @@ class MMFilesWalMarker;
 namespace transaction {
 class Methods;
 }
-;
 class TransactionCollection;
 
 /// @brief transaction type

arangod/StorageEngine/StorageEngine.h

@@ -45,6 +45,10 @@ class PhysicalCollection;
 class TransactionCollection;
 class TransactionState;
 
+namespace transaction {
+class ContextData;
+}
+
 class StorageEngine : public application_features::ApplicationFeature {
  public:
 
@@ -71,6 +75,7 @@ class StorageEngine : public application_features::ApplicationFeature {
   virtual void start() {}
   virtual void stop() {}
 
+  virtual transaction::ContextData* createTransactionContextData() = 0;
   virtual TransactionState* createTransactionState(TRI_vocbase_t*) = 0;
   virtual TransactionCollection* createTransactionCollection(TransactionState*, TRI_voc_cid_t, AccessMode::Type, int nestingLevel) = 0;
 

arangod/Transaction/Context.cpp

@@ -27,6 +27,9 @@
 #include "MMFiles/MMFilesCollection.h"
 #include "MMFiles/MMFilesDitch.h"
 #include "RestServer/TransactionManagerFeature.h"
+#include "StorageEngine/EngineSelectorFeature.h"
+#include "StorageEngine/StorageEngine.h"
+#include "Transaction/ContextData.h"
 #include "Transaction/Helpers.h"
 #include "Transaction/Methods.h"
 #include "Utils/CollectionNameResolver.h"
@@ -68,7 +71,6 @@ transaction::Context::Context(TRI_vocbase_t* vocbase)
     : _vocbase(vocbase), 
       _resolver(nullptr), 
       _customTypeHandler(),
-      _ditches(),
       _builders{_arena},
       _stringBuffer(),
       _options(arangodb::velocypack::Options::Defaults),
@@ -85,13 +87,6 @@ transaction::Context::~Context() {
     TransactionManagerFeature::MANAGER->unregisterTransaction(_transaction.id, _transaction.hasFailedOperations);
   }
 
-  for (auto& it : _ditches) {
-    // we're done with this ditch
-    auto& ditch = it.second;
-    ditch->ditches()->freeMMFilesDocumentDitch(ditch, true /* fromTransaction */);
-    // If some external entity is still using the ditch, it is kept!
-  }
-
   // free all VPackBuilders we handed out
   for (auto& it : _builders) {
     delete it;
@@ -111,37 +106,12 @@ VPackCustomTypeHandler* transaction::Context::createCustomTypeHandler(TRI_vocbas
   
 /// @brief pin data for the collection
 void transaction::Context::pinData(LogicalCollection* collection) {
-  TRI_voc_cid_t cid = collection->cid();
+  contextData()->pinData(collection);
-
-  auto it = _ditches.find(cid);
-
-  if (it != _ditches.end()) {
-    // tell everyone else this ditch is still in use,
-    // at least until the transaction is over
-    TRI_ASSERT((*it).second->usedByTransaction());
-    // ditch already exists
-    return;
-  }
-
-  // this method will not throw, but may return a nullptr
-  auto ditch = arangodb::MMFilesCollection::toMMFilesCollection(collection)->ditches()->createMMFilesDocumentDitch(true, __FILE__, __LINE__);
-
-  if (ditch == nullptr) {
-    THROW_ARANGO_EXCEPTION(TRI_ERROR_OUT_OF_MEMORY);
-  }
-
-  try {
-    _ditches.emplace(cid, ditch);
-  }
-  catch (...) {
-    ditch->ditches()->freeMMFilesDocumentDitch(ditch, true);
-    throw;
-  }
 }
 
 /// @brief whether or not the data for the collection is pinned
-bool transaction::Context::isPinned(TRI_voc_cid_t cid) const {
+bool transaction::Context::isPinned(TRI_voc_cid_t cid) {
-  return (_ditches.find(cid) != _ditches.end());
+  return contextData()->isPinned(cid);
 }
   
 /// @brief temporarily lease a StringBuffer object
@@ -221,3 +191,10 @@ void transaction::Context::storeTransactionResult(TRI_voc_tid_t id, bool hasFail
   _transaction.hasFailedOperations = hasFailedOperations;
 }
   
+transaction::ContextData* transaction::Context::contextData() {
+  if (_contextData == nullptr) {
+    StorageEngine* engine = EngineSelectorFeature::ENGINE;
+    _contextData.reset(engine->createTransactionContextData());
+  }
+  return _contextData.get();
+}

arangod/Transaction/Context.h

@@ -43,11 +43,11 @@ struct CustomTypeHandler;
 }
 
 class CollectionNameResolver;
-class MMFilesDocumentDitch;
 class LogicalCollection;
 class TransactionState;
 
 namespace transaction {
+class ContextData;
 class Methods;
 
 class Context {
@@ -77,7 +77,7 @@ class Context {
   void pinData(arangodb::LogicalCollection*);
 
   /// @brief whether or not the data for the collection is pinned
-  bool isPinned(TRI_voc_cid_t) const;
+  bool isPinned(TRI_voc_cid_t);
   
   /// @brief temporarily lease a StringBuffer object
   basics::StringBuffer* leaseStringBuffer(size_t initialSize);
@@ -125,6 +125,8 @@ class Context {
   /// @brief create a resolver
   CollectionNameResolver const* createResolver();
 
+  transaction::ContextData* contextData();
+ 
  protected:
   
   TRI_vocbase_t* _vocbase; 
@@ -133,8 +135,6 @@ class Context {
   
   std::shared_ptr<velocypack::CustomTypeHandler> _customTypeHandler;
   
-  std::unordered_map<TRI_voc_cid_t, MMFilesDocumentDitch*> _ditches;
-
   SmallVector<arangodb::velocypack::Builder*, 32>::allocator_type::arena_type _arena;
   SmallVector<arangodb::velocypack::Builder*, 32> _builders;
   
@@ -143,6 +143,8 @@ class Context {
   arangodb::velocypack::Options _options;
   arangodb::velocypack::Options _dumpOptions;
   
+  std::unique_ptr<transaction::ContextData> _contextData;
+
   struct {
     TRI_voc_tid_t id; 
     bool hasFailedOperations;

arangod/Transaction/ContextData.h

@@ -0,0 +1,59 @@
+////////////////////////////////////////////////////////////////////////////////
+/// DISCLAIMER
+///
+/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
+/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is ArangoDB GmbH, Cologne, Germany
+///
+/// @author Jan Steemann
+////////////////////////////////////////////////////////////////////////////////
+
+#ifndef ARANGOD_TRANSACTION_CONTEXT_DATA_H
+#define ARANGOD_TRANSACTION_CONTEXT_DATA_H 1
+
+#include "Basics/Common.h"
+#include "VocBase/voc-types.h"
+
+namespace arangodb {
+class LogicalCollection;
+
+namespace transaction {
+class ContextData {
+ public:
+  ContextData(ContextData const&) = delete;
+  ContextData& operator=(ContextData const&) = delete;
+
+ protected:
+
+  /// @brief create the context data
+  ContextData() = default;
+
+ public:
+
+  /// @brief destroy the context data
+  virtual ~ContextData() = default;
+  
+  /// @brief pin data for the collection
+  virtual void pinData(arangodb::LogicalCollection*) = 0;
+
+  /// @brief whether or not the data for the collection is pinned
+  virtual bool isPinned(TRI_voc_cid_t) const = 0;
+};
+
+}
+}
+
+#endif