SERVER-13635: ExtentManager no longer needed for stats in Database

Author: erh

src/mongo/db/catalog/database.cpp

@@ -47,14 +47,10 @@
 #include "mongo/db/instance.h"
 #include "mongo/db/introspect.h"
 #include "mongo/db/pdfile.h"
-#include "mongo/db/query/internal_plans.h"
-#include "mongo/db/ops/delete.h"
 #include "mongo/db/server_parameters.h"
-#include "mongo/db/storage/data_file.h"
-#include "mongo/db/storage/extent.h"
-#include "mongo/db/storage/extent_manager.h"
-#include "mongo/db/storage/mmap_v1/mmap_v1_engine.h"
-#include "mongo/db/storage/mmap_v1/mmap_v1_extent_manager.h"
+#include "mongo/db/storage/data_file.h" //XXX
+#include "mongo/db/storage/mmap_v1/mmap_v1_engine.h" //XXX
+#include "mongo/db/storage/mmap_v1/mmap_v1_extent_manager.h" //XXX
 #include "mongo/db/storage_options.h"
 #include "mongo/db/catalog/collection.h"
 
@@ -256,11 +252,8 @@ namespace mongo {
     }
 
     void Database::getStats( OperationContext* opCtx, BSONObjBuilder* output, double scale ) {
-        bool empty = _dbEntry->isEmpty() || getExtentManager()->numFiles() == 0;
-
         list<string> collections;
-        if ( !empty )
-            _dbEntry->getCollectionNamespaces( &collections );
+        _dbEntry->getCollectionNamespaces( &collections );
 
         long long ncollections = 0;
         long long objects = 0;
@@ -298,16 +291,8 @@ namespace mongo {
         output->appendNumber( "numExtents" , numExtents );
         output->appendNumber( "indexes" , indexes );
         output->appendNumber( "indexSize" , indexSize / scale );
-        _dbEntry->appendExtraStats( output, scale );
-
-        BSONObjBuilder dataFileVersion( output->subobjStart( "dataFileVersion" ) );
-        if ( !empty ) {
-            int major, minor;
-            getFileFormat( opCtx, &major, &minor );
-            dataFileVersion.append( "major", major );
-            dataFileVersion.append( "minor", minor );
-        }
-        dataFileVersion.done();
+
+        _dbEntry->appendExtraStats( opCtx, output, scale );
     }
 
     Status Database::dropCollection( OperationContext* txn, const StringData& fullns ) {

src/mongo/db/catalog/database_catalog_entry.h

@@ -52,13 +52,16 @@ namespace mongo {
 
         virtual bool isEmpty() const = 0;
 
-        virtual void appendExtraStats( BSONObjBuilder* out, double scale ) const = 0;
+        virtual void appendExtraStats( OperationContext* opCtx,
+                                       BSONObjBuilder* out,
+                                       double scale ) const = 0;
 
         // ----
 
         virtual void getCollectionNamespaces( std::list<std::string>* out ) const = 0;
 
-        virtual Status dropCollection( OperationContext* txn, const StringData& ns ) = 0;
+        virtual Status dropCollection( OperationContext* opCtx,
+                                       const StringData& ns ) = 0;
 
     private:
         std::string _name;

src/mongo/db/storage/mmap_v1/mmap_v1_engine.cpp

@@ -288,7 +288,9 @@ namespace mongo {
         return Status::OK();
     }
 
-    void MMAP1DatabaseCatalogEntry::appendExtraStats( BSONObjBuilder* output, double scale ) const {
+    void MMAP1DatabaseCatalogEntry::appendExtraStats( OperationContext* opCtx,
+                                                      BSONObjBuilder* output,
+                                                      double scale ) const {
         if ( isEmpty() ) {
             output->appendNumber( "fileSize", 0 );
         }
@@ -306,6 +308,18 @@ namespace mongo {
             extentFreeList.appendNumber( "totalSize",
                                          static_cast<long long>( freeListSpace / scale ) );
             extentFreeList.done();
+
+            {
+
+                int major = 0;
+                int minor = 0;
+                _extentManager.getFileFormat( opCtx, &major, &minor );
+
+                BSONObjBuilder dataFileVersion( output->subobjStart( "dataFileVersion" ) );
+                dataFileVersion.append( "major", major );
+                dataFileVersion.append( "minor", minor );
+                dataFileVersion.done();
+            }
         }
 
     }

src/mongo/db/storage/mmap_v1/mmap_v1_engine.h

@@ -61,7 +61,9 @@ namespace mongo {
         bool exists() const { return _namespaceIndex.pathExists(); }
         bool isEmpty() const { return !_namespaceIndex.allocated(); }
 
-        virtual void appendExtraStats( BSONObjBuilder* out, double scale ) const;
+        virtual void appendExtraStats( OperationContext* opCtx,
+                                       BSONObjBuilder* out,
+                                       double scale ) const;
 
         Status createCollection( OperationContext* txn,
                                  const StringData& ns,

src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.cpp

@@ -552,4 +552,11 @@ namespace mongo {
                                      MAdvise::Sequential );
     }
 
+    void MmapV1ExtentManager::getFileFormat( OperationContext* txn, int* major, int* minor ) const {
+        if ( numFiles() == 0 )
+            return;
+        const DataFile* df = _getOpenFile( 0 );
+        *major = df->getHeader()->version;
+        *minor = df->getHeader()->versionMinor;
+    }
 }

src/mongo/db/storage/mmap_v1/mmap_v1_extent_manager.h

@@ -143,6 +143,8 @@ namespace mongo {
          */
         Extent* getExtent( const DiskLoc& loc, bool doSanityCheck = true ) const;
 
+        void getFileFormat( OperationContext* txn, int* major, int* minor ) const;
+
         virtual int maxSize() const;