SERVER-13084: remove NamespaceDetails::emptyCappedCollection and replace with Collection::truncate

13 files changed, 109 insertions, 76 deletions

diff --git a/src/mongo/db/auth/role_graph_update.cpp b/src/mongo/db/auth/role_graph_update.cpp
index c1f0e7c834f..873c36b54f2 100644
--- a/src/mongo/db/auth/role_graph_update.cpp
+++ b/src/mongo/db/auth/role_graph_update.cpp
@@ -261,7 +261,7 @@ namespace {
         if (cmdName == "dropIndexes" || cmdName == "deleteIndexes") {
             return Status::OK();
         }
-        if ((cmdName == "collMod" || cmdName == "emptyCappedCollection") &&
+        if ((cmdName == "collMod" || cmdName == "emptycapped") &&
             cmdObj.firstElement().str() != rolesCollectionNamespace.coll()) {
 
             // We don't care about these if they're not on the roles collection.
diff --git a/src/mongo/db/catalog/collection.cpp b/src/mongo/db/catalog/collection.cpp
index 13dc154775a..d8a76819dd0 100644
--- a/src/mongo/db/catalog/collection.cpp
+++ b/src/mongo/db/catalog/collection.cpp
@@ -460,4 +460,45 @@ namespace mongo {
         return _details->dataSize();
     }
 
+    /**
+     * order will be:
+     * 1) store index specs
+     * 2) drop indexes
+     * 3) truncate record store
+     * 4) re-write indexes
+     */
+    Status Collection::truncate() {
+        massert( 17431, "index build in progress", _indexCatalog.numIndexesInProgress() == 0 );
+
+        // 1) store index specs
+        vector<BSONObj> indexSpecs;
+        {
+            IndexCatalog::IndexIterator ii = _indexCatalog.getIndexIterator( false );
+            while ( ii.more() ) {
+                const IndexDescriptor* idx = ii.next();
+                indexSpecs.push_back( idx->infoObj().getOwned() );
+            }
+        }
+
+        // 2) drop indexes
+        Status status = _indexCatalog.dropAllIndexes( true );
+        if ( !status.isOK() )
+            return status;
+        _cursorCache.invalidateAll( false );
+        _infoCache.reset();
+
+        // 3) truncate record store
+        status = _recordStore->truncate();
+        if ( !status.isOK() )
+            return status;
+
+        // 4) re-create indexes
+        for ( size_t i = 0; i < indexSpecs.size(); i++ ) {
+            status = _indexCatalog.createIndex( indexSpecs[i], false );
+            if ( !status.isOK() )
+                return status;
+        }
+
+        return Status::OK();
+    }
 }
diff --git a/src/mongo/db/catalog/collection.h b/src/mongo/db/catalog/collection.h
index fe0364bf15e..615ea282290 100644
--- a/src/mongo/db/catalog/collection.h
+++ b/src/mongo/db/catalog/collection.h
@@ -182,6 +182,12 @@ namespace mongo {
 
         StatusWith<CompactStats> compact( const CompactOptions* options );
 
+        /**
+         * removes all documents as fast as possible
+         * indexes before and after will be the same
+         * as will other characteristics
+         */
+        Status truncate();
         // -----------
 
 
diff --git a/src/mongo/db/commands/test_commands.cpp b/src/mongo/db/commands/test_commands.cpp
index 208f39619bd..ef4fc7c02c2 100644
--- a/src/mongo/db/commands/test_commands.cpp
+++ b/src/mongo/db/commands/test_commands.cpp
@@ -191,7 +191,9 @@ namespace mongo {
 
             std::vector<BSONObj> indexes = stopIndexBuilds(cc().database(), cmdObj);
 
-            collection->details()->emptyCappedCollection( nss.ns().c_str() );
+            Status status = collection->truncate();
+            if ( !status.isOK() )
+                return appendCommandStatus( result, status );
 
             IndexBuilder::restoreIndexes(indexes);
 
diff --git a/src/mongo/db/repl/rs_initialsync.cpp b/src/mongo/db/repl/rs_initialsync.cpp
index 0d7a92055b9..28066d1175a 100644
--- a/src/mongo/db/repl/rs_initialsync.cpp
+++ b/src/mongo/db/repl/rs_initialsync.cpp
@@ -133,7 +133,7 @@ namespace mongo {
             return; // already empty, ok.
 
         LOG(1) << "replSet empty oplog" << rsLog;
-        collection->details()->emptyCappedCollection(rsoplog);
+        uassertStatusOK( collection->truncate() );
     }
 
     bool Member::syncable() const {
diff --git a/src/mongo/db/repl/rs_rollback.cpp b/src/mongo/db/repl/rs_rollback.cpp
index e63a326937d..d92e37fa213 100644
--- a/src/mongo/db/repl/rs_rollback.cpp
+++ b/src/mongo/db/repl/rs_rollback.cpp
@@ -529,7 +529,7 @@ namespace mongo {
                                     catch(DBException& e) {
                                         if( e.getCode() == 13415 ) {
                                             // hack: need to just make cappedTruncate do this...
-                                            nsd->emptyCappedCollection(d.ns);
+                                            uassertStatusOK( collection->truncate() );
                                         }
                                         else {
                                             throw;
diff --git a/src/mongo/db/structure/catalog/cap.cpp b/src/mongo/db/structure/catalog/cap.cpp
index e62cce0edad..d103869f092 100644
--- a/src/mongo/db/structure/catalog/cap.cpp
+++ b/src/mongo/db/structure/catalog/cap.cpp
@@ -426,74 +426,4 @@ namespace mongo {
         }
     }
 
-    void NamespaceDetails::emptyCappedCollection( const char *ns ) {
-        massert( 13424, "collection must be capped", isCapped() );
-        massert( 13425, "background index build in progress", !_indexBuildsInProgress );
-
-        vector<BSONObj> indexes = Helpers::findAll( NamespaceString(ns).getSystemIndexesCollection(),
-                                                    BSON( "ns" << ns ) );
-        for ( unsigned i=0; i<indexes.size(); i++ ) {
-            indexes[i] = indexes[i].copy();
-        }
-
-        if ( _nIndexes ) {
-            Collection* collection = cc().database()->getCollection( ns );
-            verify( collection );
-            Status status = collection->getIndexCatalog()->dropAllIndexes( true );
-            massert( 13426,
-                     str::stream() << "failed index drop: " << status.toString(),
-                     status.isOK() );
-        }
-
-        // Clear all references to this namespace.
-        Collection* collection = cc().database()->getCollection( ns );
-        collection->cursorCache()->invalidateAll( false );
-        verify( collection->details() == this );
-        collection->infoCache()->reset();
-
-        // Get a writeable reference to 'this' and reset all pertinent
-        // attributes.
-        NamespaceDetails *t = writingWithoutExtra();
-
-        t->cappedLastDelRecLastExtent() = DiskLoc();
-        t->cappedListOfAllDeletedRecords() = DiskLoc();
-
-        // preserve firstExtent/lastExtent
-        t->_capExtent = _firstExtent;
-        t->_stats.datasize = _stats.nrecords = 0;
-        // lastExtentSize preserve
-        // nIndexes preserve 0
-        // capped preserve true
-        // max preserve
-        t->_paddingFactor = 1.0;
-        t->_systemFlags = 0;
-        t->_capFirstNewRecord = DiskLoc();
-        t->_capFirstNewRecord.setInvalid();
-        t->cappedLastDelRecLastExtent().setInvalid();
-        // dataFileVersion preserve
-        // indexFileVersion preserve
-        t->_multiKeyIndexBits = 0;
-        t->_reservedA = 0;
-        t->_extraOffset = 0;
-        // indexBuildInProgress preserve 0
-        memset(t->_reserved, 0, sizeof(t->_reserved));
-
-        // Reset all existing extents and recreate the deleted list.
-        for( DiskLoc ext = _firstExtent; !ext.isNull(); ext = ext.ext()->xnext ) {
-            DiskLoc prev = ext.ext()->xprev;
-            DiskLoc next = ext.ext()->xnext;
-            DiskLoc empty = ext.ext()->reuse( ns, true );
-            ext.ext()->xprev.writing() = prev;
-            ext.ext()->xnext.writing() = next;
-            addDeletedRec( empty.drec(), empty );
-        }
-
-        for ( unsigned i=0; i<indexes.size(); i++ ) {
-            IndexCatalog* ic = collection->getIndexCatalog();
-            Status status = ic->createIndex( indexes[i], false );
-            uassertStatusOK( status );
-        }
-        
-    }
-
 }
diff --git a/src/mongo/db/structure/catalog/namespace_details.h b/src/mongo/db/structure/catalog/namespace_details.h
index a294c784e19..10659d7803a 100644
--- a/src/mongo/db/structure/catalog/namespace_details.h
+++ b/src/mongo/db/structure/catalog/namespace_details.h
@@ -234,8 +234,6 @@ namespace mongo {
          * @param inclusive - Truncate 'end' as well iff true
          */
         void cappedTruncateAfter(const char *ns, DiskLoc end, bool inclusive);
-        /** Remove all documents from the capped collection */
-        void emptyCappedCollection(const char *ns);
 
         /* when a background index build is in progress, we don't count the index in nIndexes until
            complete, yet need to still use it in _indexRecord() - thus we use this function for that.
diff --git a/src/mongo/db/structure/record_store.h b/src/mongo/db/structure/record_store.h
index 6d8cb7c1001..6eca53d8a5d 100644
--- a/src/mongo/db/structure/record_store.h
+++ b/src/mongo/db/structure/record_store.h
@@ -48,6 +48,8 @@ namespace mongo {
         RecordStore( const StringData& ns );
         virtual ~RecordStore();
 
+        // CRUD related
+
         virtual Record* recordFor( const DiskLoc& loc ) const = 0;
 
         virtual void deleteRecord( const DiskLoc& dl ) = 0;
@@ -56,6 +58,13 @@ namespace mongo {
 
         virtual StatusWith<DiskLoc> insertRecord( const DocWriter* doc, int quotaMax ) = 0;
 
+        // higher level
+
+        /**
+         * removes all Records
+         */
+        virtual Status truncate() = 0;
+
         // TODO: this makes me sad, it shouldn't be in the interface
         // do not use this anymore
         virtual void increaseStorageSize( int size, int quotaMax ) = 0;
diff --git a/src/mongo/db/structure/record_store_v1_capped.cpp b/src/mongo/db/structure/record_store_v1_capped.cpp
index 183a6bfff98..36b29acb1c6 100644
--- a/src/mongo/db/structure/record_store_v1_capped.cpp
+++ b/src/mongo/db/structure/record_store_v1_capped.cpp
@@ -70,4 +70,44 @@ namespace mongo {
                                     "no space in capped collection" );
     }
 
+    Status CappedRecordStoreV1::truncate() {
+        // Get a writeable reference to 'this' and reset all pertinent
+        // attributes.
+        NamespaceDetails* t = _details->writingWithoutExtra();
+
+        t->cappedLastDelRecLastExtent() = DiskLoc();
+        t->cappedListOfAllDeletedRecords() = DiskLoc();
+
+        // preserve firstExtent/lastExtent
+        t->_capExtent = t->_firstExtent;
+        t->_stats.datasize = t->_stats.nrecords = 0;
+        // lastExtentSize preserve
+        // nIndexes preserve 0
+        // capped preserve true
+        // max preserve
+        t->_paddingFactor = 1.0;
+        t->_systemFlags = 0;
+        t->_capFirstNewRecord = DiskLoc();
+        t->_capFirstNewRecord.setInvalid();
+        t->cappedLastDelRecLastExtent().setInvalid();
+        // dataFileVersion preserve
+        // indexFileVersion preserve
+        t->_multiKeyIndexBits = 0;
+        t->_reservedA = 0;
+        t->_extraOffset = 0;
+        // indexBuildInProgress preserve 0
+        memset(t->_reserved, 0, sizeof(t->_reserved));
+
+        // Reset all existing extents and recreate the deleted list.
+        for( DiskLoc ext = t->_firstExtent; !ext.isNull(); ext = ext.ext()->xnext ) {
+            DiskLoc prev = ext.ext()->xprev;
+            DiskLoc next = ext.ext()->xnext;
+            DiskLoc empty = ext.ext()->reuse( _ns, true );
+            ext.ext()->xprev.writing() = prev;
+            ext.ext()->xnext.writing() = next;
+            _details->addDeletedRec( empty.drec(), empty );
+        }
+
+        return Status::OK();
+    }
 }
diff --git a/src/mongo/db/structure/record_store_v1_capped.h b/src/mongo/db/structure/record_store_v1_capped.h
index 5b4e9fc056d..0ce454e6812 100644
--- a/src/mongo/db/structure/record_store_v1_capped.h
+++ b/src/mongo/db/structure/record_store_v1_capped.h
@@ -49,6 +49,8 @@ namespace mongo {
 
         virtual ~CappedRecordStoreV1();
 
+        virtual Status truncate();
+
     protected:
         virtual StatusWith<DiskLoc> allocRecord( int lengthWithHeaders, int quotaMax );
 
diff --git a/src/mongo/db/structure/record_store_v1_simple.cpp b/src/mongo/db/structure/record_store_v1_simple.cpp
index 37750c8759a..f9b987072f4 100644
--- a/src/mongo/db/structure/record_store_v1_simple.cpp
+++ b/src/mongo/db/structure/record_store_v1_simple.cpp
@@ -237,4 +237,8 @@ namespace mongo {
         return StatusWith<DiskLoc>( ErrorCodes::InternalError, "cannot allocate space" );
     }
 
+    Status SimpleRecordStoreV1::truncate() {
+        return Status( ErrorCodes::InternalError,
+                       "SimpleRecordStoreV1::truncate not implemented" );
+    }
 }
diff --git a/src/mongo/db/structure/record_store_v1_simple.h b/src/mongo/db/structure/record_store_v1_simple.h
index 8173db053c0..f00ab8e7858 100644
--- a/src/mongo/db/structure/record_store_v1_simple.h
+++ b/src/mongo/db/structure/record_store_v1_simple.h
@@ -45,6 +45,7 @@ namespace mongo {
 
         virtual ~SimpleRecordStoreV1();
 
+        virtual Status truncate();
     protected:
         virtual StatusWith<DiskLoc> allocRecord( int lengthWithHeaders, int quotaMax );