ndb: fix blob performance in long transactions

ndb/include/ndbapi/NdbConnection.hpp:
  fix blob performance in long transactions
ndb/src/ndbapi/NdbConnection.cpp:
  fix blob performance in long transactions
ndb/test/ndbapi/testBlobs.cpp:
  fix blob performance in long transactions

ndb/include/ndbapi/NdbConnection.hpp

@@ -607,8 +607,8 @@ private:
   NdbOperation*	theLastExecOpInList;	    // Last executing operation in list.
 
 
-  NdbOperation*	theCompletedFirstOp;	    // First operation in completed 
-                                            // operation list.
+  NdbOperation*	theCompletedFirstOp;	    // First & last operation in completed 
+  NdbOperation*	theCompletedLastOp;         // operation list.
 
   Uint32	theNoOfOpSent;				// How many operations have been sent	    
   Uint32	theNoOfOpCompleted;			// How many operations have completed

ndb/src/ndbapi/NdbConnection.cpp

@@ -55,6 +55,7 @@ NdbConnection::NdbConnection( Ndb* aNdb ) :
   theFirstExecOpInList(NULL),
   theLastExecOpInList(NULL),
   theCompletedFirstOp(NULL),
+  theCompletedLastOp(NULL),
   theNoOfOpSent(0),
   theNoOfOpCompleted(0),
   theNoOfOpFetched(0),
@@ -124,6 +125,7 @@ NdbConnection::init()
   theLastExecOpInList	  = NULL;
 
   theCompletedFirstOp	  = NULL;
+  theCompletedLastOp	  = NULL;
 
   theGlobalCheckpointId   = 0;
   theCommitStatus         = Started;
@@ -256,6 +258,8 @@ NdbConnection::handleExecuteCompletion()
   if (tLastExecOp != NULL) {
     tLastExecOp->next(theCompletedFirstOp);
     theCompletedFirstOp = tFirstExecOp;
+    if (theCompletedLastOp == NULL)
+      theCompletedLastOp = tLastExecOp;
     theFirstExecOpInList = NULL;
     theLastExecOpInList = NULL;
   }//if
@@ -292,6 +296,8 @@ NdbConnection::execute(ExecType aTypeOfExec,
 
   ExecType tExecType;
   NdbOperation* tPrepOp;
+  NdbOperation* tCompletedFirstOp = NULL;
+  NdbOperation* tCompletedLastOp = NULL;
 
   int ret = 0;
   do {
@@ -314,6 +320,7 @@ NdbConnection::execute(ExecType aTypeOfExec,
       }
       tPrepOp = tPrepOp->next();
     }
+
     // save rest of prepared ops if batch
     NdbOperation* tRestOp= 0;
     NdbOperation* tLastOp= 0;
@@ -323,6 +330,7 @@ NdbConnection::execute(ExecType aTypeOfExec,
       tLastOp = theLastOpInList;
       theLastOpInList = tPrepOp;
     }
+
     if (tExecType == Commit) {
       NdbOperation* tOp = theCompletedFirstOp;
       while (tOp != NULL) {
@@ -338,6 +346,19 @@ NdbConnection::execute(ExecType aTypeOfExec,
       }
     }
 
+    // completed ops are in unspecified order
+    if (theCompletedFirstOp != NULL) {
+      if (tCompletedFirstOp == NULL) {
+        tCompletedFirstOp = theCompletedFirstOp;
+        tCompletedLastOp = theCompletedLastOp;
+      } else {
+        tCompletedLastOp->next(theCompletedFirstOp);
+        tCompletedLastOp = theCompletedLastOp;
+      }
+      theCompletedFirstOp = NULL;
+      theCompletedLastOp = NULL;
+    }
+
     if (executeNoBlobs(tExecType, abortOption, forceSend) == -1)
         ret = -1;
 #ifndef VM_TRACE
@@ -362,6 +383,7 @@ NdbConnection::execute(ExecType aTypeOfExec,
         tOp = tOp->next();
       }
     }
+
     // add saved prepared ops if batch
     if (tPrepOp != NULL && tRestOp != NULL) {
       if (theFirstOpInList == NULL)
@@ -373,6 +395,18 @@ NdbConnection::execute(ExecType aTypeOfExec,
     assert(theFirstOpInList == NULL || tExecType == NoCommit);
   } while (theFirstOpInList != NULL || tExecType != aTypeOfExec);
 
+  if (tCompletedFirstOp != NULL) {
+    tCompletedLastOp->next(theCompletedFirstOp);
+    theCompletedFirstOp = tCompletedFirstOp;
+    if (theCompletedLastOp == NULL)
+      theCompletedLastOp = tCompletedLastOp;
+  }
+#if ndb_api_count_completed_ops_after_blob_execute
+  { NdbOperation* tOp; unsigned n = 0;
+    for (tOp = theCompletedFirstOp; tOp != NULL; tOp = tOp->next()) n++;
+    ndbout << "completed ops: " << n << endl;
+  }
+#endif
   DBUG_RETURN(ret);
 }
 
@@ -894,6 +928,7 @@ NdbConnection::releaseOperations()
   releaseOps(theFirstExecOpInList);
 
   theCompletedFirstOp = NULL;
+  theCompletedLastOp = NULL;
   theFirstOpInList = NULL;
   theFirstExecOpInList = NULL;
   theLastOpInList = NULL;
@@ -909,6 +944,7 @@ NdbConnection::releaseCompletedOperations()
 {
   releaseOps(theCompletedFirstOp);
   theCompletedFirstOp = NULL;
+  theCompletedLastOp = NULL;
 }//NdbConnection::releaseOperations()
 
 /******************************************************************************