ParallelDebugOutput: only use parallel output when mpi size > 1.

opm/autodiff/ParallelDebugOutput.hpp

@@ -48,6 +48,7 @@ namespace Opm
         virtual const SimulatorState& globalReservoirState() const = 0 ;
         virtual const WellState& globalWellState() const = 0 ;
         virtual bool isIORank() const = 0;
+        virtual bool isParallel() const = 0;
         virtual int numCells() const = 0 ;
         virtual const int* globalCell() const = 0;
     };
@@ -79,6 +80,7 @@ namespace Opm
         virtual const SimulatorState& globalReservoirState() const { return *globalState_; }
         virtual const WellState& globalWellState() const { return *wellState_; }
         virtual bool isIORank () const { return true; }
+        virtual bool isParallel () const { return false; }
         virtual int numCells() const { return grid_.number_of_cells; }
         virtual const int* globalCell() const { return grid_.global_cell; }
     };
@@ -221,6 +223,8 @@ namespace Opm
               isIORank_( otherGrid.comm().rank() == ioRank )
         {
             const CollectiveCommunication& comm = otherGrid.comm();
+            if( comm.size() > 1 )
+            {
                 std::set< int > send, recv;
                 // the I/O rank receives from all other ranks
                 if( isIORank() )
@@ -300,6 +304,7 @@ namespace Opm
                 DistributeIndexMapping distIndexMapping( globalIndex_, otherGrid.globalCell(), localIndexMap_, indexMaps_ );
                 toIORankComm_.exchange( distIndexMapping );
             }
+        }
 
         class PackUnPackSimulatorState : public P2PCommunicatorType::DataHandleInterface
         {
@@ -533,6 +538,11 @@ namespace Opm
             return isIORank_;
         }
 
+        bool isParallel() const
+        {
+            return toIORankComm_.size() > 1;
+        }
+
         int numCells () const { return globalIndex_.size(); }
         const int* globalCell () const
         {
@@ -545,7 +555,6 @@ namespace Opm
         IndexMapType                    globalIndex_;
         IndexMapType                    localIndexMap_;
         IndexMapStorageType             indexMaps_;
-        //BlackoilState                   globalReservoirState_;
         SimulatorState                  globalReservoirState_;
         // this needs to be revised
         WellStateFullyImplicitBlackoil  globalWellState_;

opm/autodiff/SimulatorFullyImplicitBlackoilOutput.cpp

@@ -261,18 +261,19 @@ namespace Opm
             vtkWriter_->writeTimeStep( timer, localState, localWellState, false );
         }
 
-        if( parallelOutput_ )
+        bool isIORank = true ;
+        if( parallelOutput_ && parallelOutput_->isParallel() )
         {
-
             // collect all solutions to I/O rank
-            const bool isIORank = parallelOutput_->collectToIORank( localState, localWellState );
+            isIORank = parallelOutput_->collectToIORank( localState, localWellState );
+        }
 
+        const SimulatorState& state = (parallelOutput_ && parallelOutput_->isParallel() ) ? parallelOutput_->globalReservoirState() : localState;
+        const WellState& wellState  = (parallelOutput_ && parallelOutput_->isParallel() ) ? parallelOutput_->globalWellState() : localWellState;
+
+        // output is only done on I/O rank
         if( isIORank )
         {
-                const SimulatorState& state = parallelOutput_->globalReservoirState();
-                const WellState& wellState  = parallelOutput_->globalWellState();
-                //std::cout << "number of wells" << wellState.bhp().size() << std::endl;
-
             // Matlab output
             if( matlabWriter_ ) {
                 matlabWriter_->writeTimeStep( timer, state, wellState, substep );
@@ -320,9 +321,8 @@ namespace Opm
                     */
                     backupfile_ << std::flush;
                 }
-                }
-            }
-        }
+            } // end backup
+        } // end isIORank
     }
 
     void