fix how pooling and get more work

client/dbclientcursor.cpp

@@ -66,14 +66,29 @@ namespace mongo {
         b.append(ns.c_str());
         b.append(nextBatchSize());
         b.append(cursorId);
-
+        
         Message toSend;
         toSend.setData(dbGetMore, b.buf(), b.len());
         auto_ptr<Message> response(new Message());
-        connector->call( toSend, *response );
+        
+        if ( connector ){
+            connector->call( toSend, *response );
+            m = response;
+            dataReceived();
+        }
+        else {
+            assert( _scopedHost.size() );
+            ScopedDbConnection conn( _scopedHost );
+            conn->call( toSend , *response );
+            connector = conn.get();
+            m = response;
+            dataReceived();
+            connector = 0;
+            conn.done();
+        }
+        
+
 
-        m = response;
-        dataReceived();
     }
 
     void DBClientCursor::dataReceived() {
@@ -136,8 +151,11 @@ namespace mongo {
     }
 
     void DBClientCursor::attach( ScopedDbConnection * conn ){
-        assert( ! _scopedConn );
-        _scopedConn = conn->steal();
+        assert( _scopedHost.size() == 0 );
+        assert( connector == conn->get() );
+        _scopedHost = conn->getHost();
+        conn->done();
+        connector = 0;
     }
 
 
@@ -154,17 +172,15 @@ namespace mongo {
                 Message m;
                 m.setData( dbKillCursors , b.buf() , b.len() );
                 
-                connector->sayPiggyBack( m );
-            }
-
-            if ( _scopedConn ){
-                if ( moreInCurrentBatch() ){
-                    log() << "warning: cursor deleted, but moreInCurrentBatch and scoped conn." << endl;
+                if ( connector ){
+                    connector->sayPiggyBack( m );
                 }
                 else {
-                    _scopedConn->done();
+                    assert( _scopedHost.size() );
+                    ScopedDbConnection conn( _scopedHost );
+                    conn->sayPiggyBack( m );
+                    conn.done();
                 }
-                delete _scopedConn;
             }
 
         );

client/dbclientcursor.h

@@ -112,8 +112,7 @@ namespace mongo {
                 nReturned(),
                 pos(),
                 data(),
-                _ownCursor( true ),
-                _scopedConn(0){
+                _ownCursor( true ){
         }
         
         DBClientCursor( DBConnector *_connector, const string &_ns, long long _cursorId, int _nToReturn, int options ) :
@@ -127,8 +126,7 @@ namespace mongo {
                 nReturned(),
                 pos(),
                 data(),
-                _ownCursor( true ),
-                _scopedConn(0){
+                _ownCursor( true ){
         }            
 
         virtual ~DBClientCursor();
@@ -165,7 +163,7 @@ namespace mongo {
         void dataReceived();
         void requestMore();
         bool _ownCursor; // see decouple()
-        ScopedDbConnection * _scopedConn;
+        string _scopedHost;
     };
     
     

jstests/sharding/shard6.js

@@ -1,12 +1,30 @@
 // shard6.js
 
-s = new ShardingTest( "shard6" , 2 , 0 , 1 );
+summary = "";
+
+s = new ShardingTest( "shard6" , 2 , 0 , 2 );
 
 s.adminCommand( { enablesharding : "test" } );
 s.adminCommand( { shardcollection : "test.data" , key : { num : 1 } } );
 
 db = s.getDB( "test" );
 
+function poolStats( where ){
+    var total = 0;
+    var msg = "poolStats " + where + " ";
+    var x = db.runCommand( "connPoolStats" ).hosts
+    for ( var h in x ){
+        var z = x[h];
+        msg += z.created + " ";
+        total += z.created
+    }
+    print( "****\n" + msg + "\n*****" )
+    summary += msg + "\n";
+    return total
+}
+
+poolStats( "at start" )
+
 // we want a lot of data, so lets make a 50k string to cheat :)
 bigString = "";
 while ( bigString.length < 50000 )
@@ -18,7 +36,9 @@ for ( ; num<100; num++ ){
     db.data.save( { num : num , bigString : bigString } );
 }
 
-assert.eq( 100 , db.data.find().toArray().length );
+assert.eq( 100 , db.data.find().toArray().length , "basic find after setup" );
+
+connBefore = poolStats( "setup done" )
 
 // limit
 
@@ -27,8 +47,11 @@ assert.eq( 1 , db.data.find().limit(1).itcount() , "limit test 2" );
 for ( var i=1; i<10; i++ ){
     assert.eq( i , db.data.find().limit(i).itcount() , "limit test 3a : " + i );
     assert.eq( i , db.data.find().skip(i).limit(i).itcount() , "limit test 3b : " + i );
+    poolStats( "after loop : " + i );
 }
 
+assert.eq( connBefore , poolStats( "limit test done"  ) , "limit test conns" );
+
 function assertOrder( start , num ){
     var a = db.data.find().skip(start).limit(num).sort( { num : 1 } ).map( function(z){ return z.num; } );
     var c = []
@@ -40,12 +63,34 @@ function assertOrder( start , num ){
 assertOrder( 0 , 10 );
 assertOrder( 5 , 10 );
 
-assert.eq( 5 , db.data.find().skip( num - 5 ).itcount() , "skip 1 " );
-assert.eq( 5 , db.data.find().skip( num - 5 ).sort( { num : 1 } ).itcount() , "skip 2 " );
-assert.eq( 5 , db.data.find().skip( num - 5 ).sort( { _id : 1 } ).itcount() , "skip 3 " );
-assert.eq( 0 , db.data.find().skip( num + 5 ).sort( { num : 1 } ).itcount() , "skip 4 " );
-assert.eq( 0 , db.data.find().skip( num + 5 ).sort( { _id : 1 } ).itcount() , "skip 5 " );
+poolStats( "after checking order" )
 
+function doItCount( skip , sort , batchSize ){
+    var c = db.data.find();
+    if ( skip )
+        c.skip( skip )
+    if ( sort )
+        c.sort( sort );
+    if ( batchSize )
+        c.batchSize( batchSize )
+    return c.itcount();
+    
+}
+
+function checkItCount( batchSize ){
+    assert.eq( 5 , doItCount( num - 5 , null , batchSize ) , "skip 1 " + batchSize );
+    assert.eq( 5 , doItCount( num - 5 , { num : 1 } , batchSize ) , "skip 2 " + batchSize );
+    assert.eq( 5 , doItCount( num - 5 , { _id : 1 } , batchSize ) , "skip 3 " + batchSize );
+    assert.eq( 0 , doItCount( num + 5 , { num : 1 } , batchSize ) , "skip 4 " + batchSize );
+    assert.eq( 0 , doItCount( num + 5 , { _id : 1 } , batchSize ) , "skip 5 " + batchSize );
+}
+
+poolStats( "before checking itcount" )
+
+checkItCount( 0 )
+checkItCount( 2 )
+
+poolStats( "after checking itcount" )
 
 // --- test save support ---
 
@@ -54,4 +99,7 @@ o.x = 16;
 db.data.save( o );
 assert.eq( 16 , db.data.findOne( { _id : o._id } ).x , "x1 - did save fail?" );
 
+poolStats( "at end" )
+
+print( summary )
 s.stop();