Example #1
0
        //
        // Main Dryad LINQ execution stuff
        //
        public int ExecLinqToDryad(string[] args)
        {
            //
            // must be at least two arguments (program name and query XML file name)
            //
            if (args.Length < 2)
            {
                DryadLogger.LogCritical(0, null, "Must provide at least query XML file name.");
                return(-1);
            }

            //
            // break if --break is included in arguments (and eliminate it, as it is not known downstream)
            //
            if (ConsumeSingleArgument("--break", ref args))
            {
                DebugHelper.WaitForDebugger();
            }

            //
            // parse the XML input, producing a DryadLINQ Query
            //
            Query           query  = new Query();
            QueryPlanParser parser = new QueryPlanParser();

            if (!parser.ParseQueryXml(args[1], query))
            {
                DryadLogger.LogCritical(0, null, "Invalid query plan");
                return(-1);
            }

            //
            // build internal app arguments
            //
            List <string> internalArgs = new List <string>();

            //
            // add the XmlExecHost args to the internal app arguments
            //
            foreach (string xmlExecHostArg in query.xmlExecHostArgs)

            {
                if (xmlExecHostArg == "--break")
                {
                    DebugHelper.WaitForDebugger();
                }
                else
                {
                    internalArgs.Add(xmlExecHostArg);
                }
            }

            //
            // combine internal arguments with any additional arguments received on the command line
            // don't include argv[0] and argv[1] (program name and query XML file name)
            //

            int internalArgc = (int)internalArgs.Count;
            int externalArgc = args.Length - 2;          // don't include argv[0] and argv[1]
            int combinedArgc = internalArgc + externalArgc;

            string[] combinedArgv = new string[combinedArgc];

            string msg = "";

            // internal arguments first
            for (int i = 0; i < internalArgc; i++)
            {
                combinedArgv[i] = internalArgs[i];
                msg            += String.Format("{0} ", combinedArgv[i]);
            }

            // then external arguments
            for (int i = 0; i < externalArgc; i++)
            {
                combinedArgv[i + internalArgc] = args[i + 2]; // don't include argv[0] and argv[1]

                msg += String.Format("{0} ", combinedArgv[i + internalArgc]);
            }
            DryadLogger.LogInformation(null, "Arguments: {0}", msg);

            string jobClass    = "DryadLINQ";
            string dryadBinDir = Environment.GetEnvironmentVariable("DRYAD_HOME");

            if (String.IsNullOrEmpty(dryadBinDir))
            {
                throw new ApplicationException("DryadLINQ requires the DRYAD_HOME environment variable to be set to the Dryad binary folder.");
            }
            string exeName = Path.Combine(dryadBinDir, "VertexHost.exe");

            // create app and run it
            //
            DrGraphParameters p = DrDefaultParameters.Make(exeName, jobClass, query.enableSpeculativeDuplication);

            DrArtemisLegacyReporter reporter = new DrArtemisLegacyReporter();

            p.m_defaultProcessTemplate.GetListenerList().Add(reporter);
            p.m_defaultVertexTemplate.GetListenerList().Add(reporter);
            p.m_topologyReporter            = reporter;
            p.m_intermediateCompressionMode = query.intermediateDataCompression;
            DrGraphExecutor graphExecutor = new DrGraphExecutor();
            DrGraph         graph         = graphExecutor.Initialize(p);

            if (graph == null)
            {
                DryadLogger.LogCritical(0, null, "Failed to initialize Graph Executor");
                return(-1);
            }
            DryadLINQApp app = new DryadLINQApp(graph);

            // Initialize with arguments
            app.SetXmlFileName(args[1]);
            if (!app.ParseCommandLineFlags(combinedArgv))
            {
                DryadLogger.LogCritical(0, null, "Bad command-line options");
                return(-1);
            }
            // Build graph from query plan
            GraphBuilder builder = new GraphBuilder();

            builder.BuildGraphFromQuery(app, query);

            // Run the app
            DryadLogger.LogInformation(null, "Running the app");

            graphExecutor.Run();
            DrError exitStatus = graphExecutor.Join();

            DryadLogger.LogInformation(null, "Finished running the app");

            if (exitStatus == null || exitStatus.m_code == 0)
            {
                FinalizeExecution(query, graph);
                DryadLogger.LogInformation(null, "Application completed successfully.");
                return(0);
            }
            else
            {
                DryadLogger.LogCritical(exitStatus.m_code, null, "Application failed with error code 0x{0:X8}.\n", exitStatus.m_code);
                return(exitStatus.m_code);
            }
        }
Example #2
0
        //
        // Main Dryad LINQ execution stuff
        //
        public int ExecLinqToDryad(string[] args)
        {
            //
            // must be at least two arguments (program name and query XML file name)
            //
            if (args.Length < 2)
            {
                DryadLogger.LogCritical(0, null, "Must provide at least query XML file name.");
                return -1;
            }

            //
            // break if --break is included in arguments (and eliminate it, as it is not known downstream)
            //
            if (ConsumeSingleArgument("--break", ref args))
            {
                DebugHelper.WaitForDebugger();
            }

            //
            // parse the XML input, producing a DryadLINQ Query
            //
            Query query = new Query();
            QueryPlanParser parser = new QueryPlanParser();
            if (!parser.ParseQueryXml(args[1], query))
            {
                DryadLogger.LogCritical(0, null, "Invalid query plan");
                return -1;
            }

            //
            // build internal app arguments
            //
            List<string> internalArgs = new List<string>();

            //
            // add the XmlExecHost args to the internal app arguments
            //
            foreach (string xmlExecHostArg in query.xmlExecHostArgs)

            {
                if (xmlExecHostArg == "--break")
                {
                    DebugHelper.WaitForDebugger();
                }
                else
                {
                    internalArgs.Add(xmlExecHostArg);
                }
            }

            //
            // combine internal arguments with any additional arguments received on the command line
            // don't include argv[0] and argv[1] (program name and query XML file name)
            //

            int internalArgc = (int)internalArgs.Count;
            int externalArgc = args.Length - 2;          // don't include argv[0] and argv[1]
            int combinedArgc = internalArgc + externalArgc;
            string[] combinedArgv = new string[combinedArgc];

            string msg = "";
            // internal arguments first
            for (int i=0; i<internalArgc; i++)
            {
                combinedArgv[i] = internalArgs[i];
                msg += String.Format("{0} ", combinedArgv[i]);
            }

            // then external arguments
            for (int i = 0; i<externalArgc; i++)
            {
                combinedArgv[i+internalArgc] = args[i+2]; // don't include argv[0] and argv[1]

                msg += String.Format("{0} ", combinedArgv[i+internalArgc]);
            }
            DryadLogger.LogInformation(null, "Arguments: {0}", msg);

            string jobClass = "DryadLINQ";
            string dryadBinDir = Environment.GetEnvironmentVariable("DRYAD_HOME");
            if (String.IsNullOrEmpty(dryadBinDir))
            {
                throw new ApplicationException("DryadLINQ requires the DRYAD_HOME environment variable to be set to the Dryad binary folder.");
            }
            string exeName = Path.Combine(dryadBinDir, "VertexHost.exe");

            // create app and run it
            //
            DrGraphParameters p = DrDefaultParameters.Make(exeName, jobClass, query.enableSpeculativeDuplication);

            DrArtemisLegacyReporter reporter = new DrArtemisLegacyReporter();
            p.m_defaultProcessTemplate.GetListenerList().Add(reporter);
            p.m_defaultVertexTemplate.GetListenerList().Add(reporter);
            p.m_topologyReporter = reporter;
            p.m_intermediateCompressionMode = query.intermediateDataCompression;
            DrGraphExecutor graphExecutor = new DrGraphExecutor();
            DrGraph graph = graphExecutor.Initialize(p);
            if (graph == null)
            {
                DryadLogger.LogCritical(0, null, "Failed to initialize Graph Executor");
                return -1;
            }
            DryadLINQApp app = new DryadLINQApp(graph);

            // Initialize with arguments
            app.SetXmlFileName(args[1]);
            if (!app.ParseCommandLineFlags(combinedArgv))
            {
                DryadLogger.LogCritical(0, null, "Bad command-line options");
                return -1;
            }
            // Build graph from query plan
            GraphBuilder builder = new GraphBuilder();
            builder.BuildGraphFromQuery(app, query);

            // Run the app
            DryadLogger.LogInformation(null, "Running the app");

            graphExecutor.Run();
            DrError exitStatus = graphExecutor.Join();

            DryadLogger.LogInformation(null, "Finished running the app");

            if (exitStatus == null || exitStatus.m_code == 0)
            {
                FinalizeExecution(query, graph);
                DryadLogger.LogInformation(null, "Application completed successfully.");
                return 0;
            }
            else
            {
                DryadLogger.LogCritical(exitStatus.m_code, null, "Application failed with error code 0x{0:X8}.\n", exitStatus.m_code);
                return exitStatus.m_code;
            }
        }
Example #3
0
        private DrInputStreamManager CreateInputNode(DryadLINQApp app, VertexInfo info, string inputName)
        {
            DrInputStreamManager s;
            int err = 0;

            DryadLogger.LogMethodEntry(inputName);

            if (info.ioType == VertexInfo.IOType.PARTITIONEDFILE)
            {
                DrPartitionInputStream input = new DrPartitionInputStream();

                err = input.Open(app.GetUniverse(), info.sources[0]);
                if (!SUCCEEDED(err))
                {
                    string msg = String.Format("Could not read DSC input file {0}", info.sources[0]);
                    throw new LinqToDryadException(msg, err);
                }

                DrManagerBase        inputStage   = new DrManagerBase(app.GetGraph(), inputName);
                DrInputStreamManager inputManager = new DrInputStreamManager(input, inputStage);

                s = inputManager;
            }
            //else if ( info.ioType == VertexInfo.IOType.STREAM )
            //{
            //    DrDscInputStream input = new DrDscInputStream();

            //    DryadLogger.LogInformation("Create input node", "Opening DSC input fileset");

            //    err = input.Open(app.GetUniverse(), info.sources[0]);
            //    if (!SUCCEEDED(err))
            //    {
            //        string msg = String.Format("Could not read DSC input fileset {0}", info.sources[0]);
            //        throw new LinqToDryadException(msg, err);
            //    }

            //    DryadLogger.LogInformation("Create input node", "Opened DSC input fileset");

            //    DrManagerBase inputStage = new DrManagerBase(app.GetGraph(), inputName);
            //    DrInputStreamManager inputManager = new DrInputStreamManager(input, inputStage);

            //    s = inputManager;
            //}
            else if (info.ioType == VertexInfo.IOType.HDFS_STREAM)
            {
                DrHdfsInputStream input = new DrHdfsInputStream();

                DryadLogger.LogInformation("Create input node", "Opening HDFS input fileset");

                err = input.Open(app.GetUniverse(), info.sources[0]);
                if (!SUCCEEDED(err))
                {
                    string msg = String.Format("Could not read HDFS input fileset {0}", info.sources[0]);
                    throw new LinqToDryadException(msg, err);
                }

                DryadLogger.LogInformation("Create input node", "Opened HDFS input fileset");

                DrManagerBase        inputStage   = new DrManagerBase(app.GetGraph(), inputName);
                DrInputStreamManager inputManager = new DrInputStreamManager(input, inputStage);

                s = inputManager;
            }
            else
            {
                string msg = String.Format("Unknown input type {0}", info.ioType);
                throw new LinqToDryadException(msg);
            }

            DryadLogger.LogMethodExit();
            return(s);
        }
Example #4
0
        public void BuildGraphFromQuery(DryadLINQApp app, Query query)
        {
            // set configurable properties
            int    highThreshold          = app.GetMaxAggregateInputs();
            int    lowThreshold           = 16;
            UInt64 highDataThreshold      = (UInt64)app.GetAggregateThreshold();
            UInt64 lowDataThreshold       = (3 * highDataThreshold) / 4;
            UInt64 maxSingleDataThreshold = highDataThreshold / 2;
            int    aggFilterThreshold     = app.GetMaxAggregateFilterInputs();

            // use a graph stage map to store the vertices as they are created, grouped by stage.
            Dictionary <int, GraphStageInfo> graphStageMap = new Dictionary <int, GraphStageInfo>();

            DryadLogger.LogInformation("Build Graph From Query", "Building graph");

            //
            // Create a set of vertices for each vertex (stage) in the query plan
            //
            DryadLogger.LogInformation("Build Graph From Query", "Adding vertices");
            foreach (KeyValuePair <int, Vertex> kvp in query.queryPlan)
            {
                Vertex         v     = kvp.Value;
                GraphStageInfo value = null;

                if (!graphStageMap.TryGetValue(v.uniqueId, out value))
                {
                    DryadLogger.LogInformation("Build Graph From Query", "Adding vertices for stage {0}", v.name);
                    CreateVertexSet(v, app, query, graphStageMap);
                }
            }

            //
            // Add dynamic stage managers
            //
            DryadLogger.LogInformation("Build Graph From Query", "Adding stage managers");
            foreach (KeyValuePair <int, GraphStageInfo> kvp in graphStageMap)
            {
                Vertex v = kvp.Value.vertex;

                //
                //There are no dynamic managers
                //
                if (v.dynamicManager == null)
                {
                    continue;
                }

                DrStageManager newManager = kvp.Value.stageManager;        // newManager

                DrGraphParameters parameters = app.GetGraph().GetParameters();

                string stdVertexName = "MW";
                string cpyVertexName = "CP";

                if (v.type != Vertex.Type.INPUTTABLE && v.type != Vertex.Type.CONCAT)
                {
                    if (v.dynamicManager.type == DynamicManager.Type.SPLITTER)
                    {
                        if (v.info.predecessors.Length == 1)
                        {
                            DrPipelineSplitManager splitter = new DrPipelineSplitManager();
                            newManager.AddDynamicConnectionManager(graphStageMap[v.info.predecessors[0].uniqueId].stageManager, splitter);
                        }
                        else
                        {
                            DrSemiPipelineSplitManager splitter = new DrSemiPipelineSplitManager();
                            newManager.AddDynamicConnectionManager(graphStageMap[v.info.predecessors[0].uniqueId].stageManager, splitter);
                        }
                    }
                    else if (v.dynamicManager.type == DynamicManager.Type.PARTIALAGGR)
                    {
                        DrDynamicAggregateManager dynamicMerge = new DrDynamicAggregateManager();

                        dynamicMerge.SetGroupingSettings(0, 0);
                        dynamicMerge.SetMachineGroupingSettings(2, aggFilterThreshold);
                        dynamicMerge.SetDataGroupingSettings(lowDataThreshold, highDataThreshold, maxSingleDataThreshold);
                        dynamicMerge.SetSplitAfterGrouping(true);

                        foreach (Predecessor p in v.info.predecessors)
                        {
                            newManager.AddDynamicConnectionManager(graphStageMap[p.uniqueId].stageManager, dynamicMerge);
                        }
                    }
                    else if (v.dynamicManager.type == DynamicManager.Type.FULLAGGR ||
                             v.dynamicManager.type == DynamicManager.Type.HASHDISTRIBUTOR)
                    {
                        int idx = 0;
                        int sz  = v.dynamicManager.assemblyNames == null ? 0 : v.dynamicManager.assemblyNames.Length;
                        DrDynamicAggregateManager dynamicMerge = new DrDynamicAggregateManager();

                        if (v.dynamicManager.type == DynamicManager.Type.FULLAGGR || sz > 1)
                        {
                            dynamicMerge = new DrDynamicAggregateManager();

                            string        name     = v.dynamicManager.methodNames[idx];
                            DrManagerBase newStage = new DrManagerBase(app.GetGraph(), name);

                            DrActiveVertex mergeVertex = new DrActiveVertex(newStage, parameters.m_defaultProcessTemplate, parameters.m_defaultVertexTemplate);
                            mergeVertex.AddArgument(stdVertexName);

                            mergeVertex.AddArgument(v.dynamicManager.assemblyNames[idx]);
                            mergeVertex.AddArgument(v.dynamicManager.classNames[idx]);
                            mergeVertex.AddArgument(v.dynamicManager.methodNames[idx]);

                            idx++;
                            dynamicMerge.SetInternalVertex(mergeVertex);

                            dynamicMerge.SetGroupingSettings(0, 0);
                            dynamicMerge.SetPodGroupingSettings(lowThreshold, highThreshold);
                            dynamicMerge.SetDataGroupingSettings(lowDataThreshold,
                                                                 highDataThreshold,
                                                                 maxSingleDataThreshold);
                            dynamicMerge.SetMaxAggregationLevel(v.dynamicManager.aggregationLevels);
                        }

                        if (v.dynamicManager.type == DynamicManager.Type.FULLAGGR)
                        {
                            newManager.AddDynamicConnectionManager(graphStageMap[v.info.predecessors[0].uniqueId].stageManager, dynamicMerge);
                        }
                        else
                        {
                            string        name     = v.dynamicManager.methodNames[idx];
                            DrManagerBase newStage = new DrManagerBase(app.GetGraph(), name);

                            DrActiveVertex distributeVertex = new DrActiveVertex(newStage, parameters.m_defaultProcessTemplate, parameters.m_defaultVertexTemplate);
                            distributeVertex.AddArgument(stdVertexName);

                            distributeVertex.AddArgument(v.dynamicManager.assemblyNames[idx]);
                            distributeVertex.AddArgument(v.dynamicManager.classNames[idx]);
                            distributeVertex.AddArgument(v.dynamicManager.methodNames[idx]);

                            idx++;

                            DrDynamicDistributionManager dynamicHashDistribute =
                                new DrDynamicDistributionManager(distributeVertex, dynamicMerge);
                            dynamicHashDistribute.SetDataPerVertex(highDataThreshold * 2);  // 2GB

                            newManager.AddDynamicConnectionManager(graphStageMap[v.info.predecessors[0].uniqueId].stageManager, dynamicHashDistribute);
                        }
                    }
                    else if (v.dynamicManager.type == DynamicManager.Type.RANGEDISTRIBUTOR)
                    {
                        DrStageManager splitManager            = graphStageMap[v.dynamicManager.splitVertexId].stageManager;
                        DrDynamicRangeDistributionManager drdm = new DrDynamicRangeDistributionManager(splitManager, v.dynamicManager.sampleRate);
                        drdm.SetDataPerVertex(highDataThreshold * 2);   // 2GB
                        newManager.AddDynamicConnectionManager(graphStageMap[v.info.predecessors[0].uniqueId].stageManager, drdm);
                    }
                    else if (v.dynamicManager.type == DynamicManager.Type.BROADCAST)
                    {
                        // the copy vertex
                        int           bcastNumber = 0;
                        string        nameString  = String.Format("CP__{0}", bcastNumber++);
                        DrManagerBase newStage    = new DrManagerBase(app.GetGraph(), nameString);

                        DrActiveVertex copyVertex =
                            new DrActiveVertex(newStage,
                                               parameters.m_defaultProcessTemplate,
                                               parameters.m_defaultVertexTemplate);
                        copyVertex.AddArgument(cpyVertexName);

                        DrDynamicBroadcastManager bcast = new DrDynamicBroadcastManager(copyVertex);
                        newManager.AddDynamicConnectionManager(graphStageMap[v.info.predecessors[0].uniqueId].stageManager, bcast);
                    }
                    else if (v.dynamicManager.type != DynamicManager.Type.NONE)
                    {
                        DryadLogger.LogWarning("Build Graph From Query", "Dynamic manager type {0} not supported yet", v.dynamicManager.type);
                    }
                }
            }


            //
            // Add all the edges
            //
            DryadLogger.LogInformation("Build Graph From Query", "Adding edges");
            foreach (KeyValuePair <int, GraphStageInfo> kvp in graphStageMap)
            {
                AddEdges(kvp.Value, graphStageMap);
            }

            //
            // Register the actual created vertices with the graph
            //
            MaterializeToManagers(graphStageMap);
        }
Example #5
0
        private void CreateVertexSet(Vertex v, DryadLINQApp app, Query query, Dictionary <int, GraphStageInfo> graphStageMap)
        {
            SortedDictionary <int, Vertex> queryPlan = query.queryPlan;
            DrVertexSet    nodes      = null;
            DrStageManager newManager = null;

            app.GetGraph().GetParameters();

            DrGraphParameters parameters    = app.GetGraph().GetParameters();
            string            stdVertexName = "MW";

            if (v.type == Vertex.Type.INPUTTABLE)
            {
                DrInputStreamManager input = CreateInputNode(app, v.info, v.name);
                newManager = input.GetStageManager();
                nodes      = CreateVertexSet(app.GetGraph(), input);
            }
            else if (v.type == Vertex.Type.OUTPUTTABLE)
            {
                DrOutputStreamManager output = CreateOutputNode(app, v.info, v.name);
                newManager = output.GetStageManager();
                nodes      = CreateVertexSet(app.GetGraph(), output, v.partitions);
            }
            else if (v.type == Vertex.Type.CONCAT)
            {
                newManager = new DrManagerBase(app.GetGraph(), v.name);

                // the set of nodes in a concat is just the set of nodes in the predecessor stages concatenated
                nodes = new DrVertexSet();
                foreach (Predecessor p in v.info.predecessors)
                {
                    GraphStageInfo value = null;
                    if (graphStageMap.TryGetValue(p.uniqueId, out value))
                    {
                        nodes.InsertRange(nodes.Count, value.members);
                    }
                    else
                    {
                        throw new LinqToDryadException(String.Format("Concat: Failed to find predecessor {0} in graph stage map", p.uniqueId));
                    }
                }
            }
            else
            {
                newManager = new DrManagerBase(app.GetGraph(), v.name);

                DrVertex vertex;
                if (v.type == Vertex.Type.TEE)
                {
                    DrTeeVertex teeVertex = new DrTeeVertex(newManager);
                    vertex = teeVertex;
                }
                else
                {
                    DrActiveVertex activeVertex = new DrActiveVertex(newManager, parameters.m_defaultProcessTemplate, parameters.m_defaultVertexTemplate);

                    activeVertex.AddArgument(stdVertexName);
                    activeVertex.AddArgument(v.info.assemblyName);
                    activeVertex.AddArgument(v.info.className);
                    activeVertex.AddArgument(v.info.methodName);

                    vertex = activeVertex;
                }

                nodes = CreateVertexSet(app.GetGraph(), vertex, v.partitions);

                if (v.machines != null && v.machines.Length != 0 && v.type != Vertex.Type.TEE)
                {
                    for (int i = 0; i < v.partitions; i++)
                    {
                        DrResource r = app.GetUniverse().LookUpResource(v.machines[i]);

                        if (r != null)
                        {
                            DrVertex       baseVertex   = nodes[i];
                            DrActiveVertex activeVertex = baseVertex as DrActiveVertex;

                            activeVertex.GetAffinity().SetHardConstraint(true);
                            activeVertex.GetAffinity().AddLocality(r);
                        }
                    }
                }

                FileStream mapfile = app.GetIdentityMapFile();
                if (mapfile != null)
                {
                    for (int i = 0; i < v.partitions; i++)
                    {
                        DrVertex jmv     = nodes[i];
                        string   message = String.Format("Mapping {0}[{1}] to {2}\n", v.uniqueId, i, jmv.GetId());
                        System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding();
                        mapfile.Seek(0, SeekOrigin.End);
                        mapfile.Write(encoding.GetBytes(message), 0, message.Length);
                    }
                }
            }

            graphStageMap.Add(v.uniqueId, new GraphStageInfo(nodes, v, newManager));
        }
Example #6
0
        private DrOutputStreamManager CreateOutputNode(DryadLINQApp app, VertexInfo info, string outputName)
        {
            DrOutputStreamManager s;

            if (info.ioType == VertexInfo.IOType.PARTITIONEDFILE)
            {
                DrPartitionOutputStream output = new DrPartitionOutputStream();
                int err = output.Open(info.sources[0], info.partitionUncPath);
                if (!SUCCEEDED(err))
                {
                    string msg = String.Format("Could not open DSC output fileset {0}", info.sources[0]);
                    throw new LinqToDryadException(msg, err);
                }

                DrManagerBase         outputStage   = new DrManagerBase(app.GetGraph(), outputName);
                DrOutputStreamManager outputManager = new DrOutputStreamManager(output, outputStage);
                app.GetGraph().AddPartitionGenerator(outputManager);

                s = outputManager;
            }
            //else if ( info.ioType == VertexInfo.IOType.STREAM )
            //{
            //    DrDscOutputStream output = new DrDscOutputStream(info.compressionScheme, info.isTemporary);
            //    int err = 0;
            //    if (info.recordType == "")
            //    {
            //        err = output.Open(info.sources[0], info.partitionUncPath);
            //    }
            //    else
            //    {
            //        err = output.OpenWithRecordType(info.sources[0], info.partitionUncPath, info.recordType);
            //    }

            //    if (!SUCCEEDED(err))
            //    {
            //        string msg = String.Format("Could not open DSC output fileset {0}", info.sources[0]);
            //        throw new LinqToDryadException(msg, err);
            //    }

            //    DrManagerBase outputStage = new DrManagerBase(app.GetGraph(), outputName);
            //    DrOutputStreamManager outputManager = new DrOutputStreamManager(output, outputStage);
            //    app.GetGraph().AddPartitionGenerator(outputManager);

            //    s = outputManager;
            //}
            else if (info.ioType == VertexInfo.IOType.HDFS_STREAM)
            {
                DrHdfsOutputStream output = new DrHdfsOutputStream();
                int err = output.Open(info.sources[0]);

                if (!SUCCEEDED(err))
                {
                    string msg = String.Format("Could not open HDFS output fileset {0}", info.sources[0]);
                    throw new LinqToDryadException(msg, err);
                }

                DrManagerBase         outputStage   = new DrManagerBase(app.GetGraph(), outputName);
                DrOutputStreamManager outputManager = new DrOutputStreamManager(output, outputStage);
                app.GetGraph().AddPartitionGenerator(outputManager);

                s = outputManager;
            }
            else
            {
                string msg = String.Format("Unknown output type {0}", info.ioType);
                throw new LinqToDryadException(msg);
            }

            return(s);
        }