SERVER-16515 change RecordAccessTracker to be per-MMAPv1 engine, not per-MMAPv1 database

4 files changed, 36 insertions, 6 deletions

diff --git a/src/mongo/db/storage/mmap_v1/mmap_v1_engine.cpp b/src/mongo/db/storage/mmap_v1/mmap_v1_engine.cpp
index 01da36dec59..5430b473c17 100644
--- a/src/mongo/db/storage/mmap_v1/mmap_v1_engine.cpp
+++ b/src/mongo/db/storage/mmap_v1/mmap_v1_engine.cpp
@@ -403,6 +403,10 @@ namespace {
         return getDur().isDurable();
     }
 
+    RecordAccessTracker& MMAPV1Engine::getRecordAccessTracker() {
+        return _recordAccessTracker;
+    }
+
     void MMAPV1Engine::cleanShutdown() {
         // wait until file preallocation finishes
         // we would only hang here if the file_allocator code generates a
diff --git a/src/mongo/db/storage/mmap_v1/mmap_v1_engine.h b/src/mongo/db/storage/mmap_v1/mmap_v1_engine.h
index 3c8ae08bcbd..9f1b42c234f 100644
--- a/src/mongo/db/storage/mmap_v1/mmap_v1_engine.h
+++ b/src/mongo/db/storage/mmap_v1/mmap_v1_engine.h
@@ -35,6 +35,7 @@
 #include <boost/thread/mutex.hpp>
 
 #include "mongo/db/storage/storage_engine.h"
+#include "mongo/db/storage/mmap_v1/record_access_tracker.h"
 
 namespace mongo {
 
@@ -71,10 +72,22 @@ namespace mongo {
         }
 
         // MMAPv1 specific (non-virtual)
-        Status repairDatabase( OperationContext* tnx,
+        Status repairDatabase( OperationContext* txn,
                                const std::string& dbName,
                                bool preserveClonedFilesOnFailure,
                                bool backupOriginalFiles );
+
+        /**
+         * Gets a reference to the abstraction used by MMAP v1 to track recently used memory
+         * addresses.
+         *
+         * MMAPv1 specific (non-virtual). This is non-const because callers are allowed to use
+         * the returned reference to modify the RecordAccessTracker.
+         *
+         * The RecordAccessTracker is thread-safe (it uses its own mutex internally).
+         */
+        RecordAccessTracker& getRecordAccessTracker();
+
     private:
         static void _listDatabases( const std::string& directory,
                                     std::vector<std::string>* out );
@@ -82,6 +95,11 @@ namespace mongo {
         boost::mutex _entryMapMutex;
         typedef std::map<std::string,MMAPV1DatabaseCatalogEntry*> EntryMap;
         EntryMap _entryMap;
+
+        // A record access tracker is essentially a large table which tracks recently used
+        // addresses. It is used when higher layers (e.g. the query system) need to ask
+        // the storage engine whether data is likely in physical memory.
+        RecordAccessTracker _recordAccessTracker;
     };
 
     void _deleteDataFiles(const std::string& database);
diff --git a/src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.cpp b/src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.cpp
index a579723a964..e958cf9182d 100644
--- a/src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.cpp
+++ b/src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.cpp
@@ -37,11 +37,13 @@
 #include "mongo/base/counter.h"
 #include "mongo/db/audit.h"
 #include "mongo/db/client.h"
+#include "mongo/db/global_environment_experiment.h"
 #include "mongo/db/storage/mmap_v1/dur.h"
 #include "mongo/db/storage/mmap_v1/data_file.h"
 #include "mongo/db/storage/mmap_v1/record.h"
 #include "mongo/db/storage/mmap_v1/extent.h"
 #include "mongo/db/storage/mmap_v1/extent_manager.h"
+#include "mongo/db/storage/mmap_v1/mmap_v1_engine.h"
 #include "mongo/db/storage/mmap_v1/mmap_v1_options.h"
 #include "mongo/db/storage/record_fetcher.h"
 #include "mongo/db/operation_context.h"
@@ -106,7 +108,10 @@ namespace mongo {
           _path(path.toString()),
           _directoryPerDB(directoryPerDB),
           _rid(RESOURCE_METADATA, dbname) {
-
+        StorageEngine* engine = getGlobalEnvironment()->getGlobalStorageEngine();
+        invariant(engine->isMmapV1());
+        MMAPV1Engine* mmapEngine = static_cast<MMAPV1Engine*>(engine);
+        _recordAccessTracker = &mmapEngine->getRecordAccessTracker();
     }
 
     boost::filesystem::path MmapV1ExtentManager::fileName( int n ) const {
@@ -261,7 +266,7 @@ namespace mongo {
 
     Record* MmapV1ExtentManager::recordForV1( const DiskLoc& loc ) const {
         Record* record = _recordForV1( loc );
-        _recordAccessTracker.markAccessed( record );
+        _recordAccessTracker->markAccessed( record );
         return record;
     }
 
@@ -277,7 +282,7 @@ namespace mongo {
             }
         }
 
-        if ( !_recordAccessTracker.checkAccessedAndMark( record ) ) {
+        if ( !_recordAccessTracker->checkAccessedAndMark( record ) ) {
             return new MmapV1RecordFetcher( record );
         }
 
@@ -300,7 +305,7 @@ namespace mongo {
         if ( doSanityCheck )
             e->assertOk();
 
-        _recordAccessTracker.markAccessed( e );
+        _recordAccessTracker->markAccessed( e );
 
         return e;
     }
diff --git a/src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.h b/src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.h
index 15958e15ef3..2c9d51a579e 100644
--- a/src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.h
+++ b/src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.h
@@ -196,7 +196,10 @@ namespace mongo {
         const std::string _path; // i.e. "/data/db"
         const bool _directoryPerDB;
         const ResourceId _rid;
-        mutable RecordAccessTracker _recordAccessTracker;
+
+        // This reference points into the MMAPv1 engine and is only valid as long as the
+        // engine is valid. Not owned here.
+        RecordAccessTracker* _recordAccessTracker;
 
         /**
          * Simple wrapper around an array object to allow append-only modification of the array,