Added lookahead scheduler.

Most scheduler now use estimated finish time instead of predicted execution time.

include/wfr/scheduling/AbstractScheduler.h

@@ -113,6 +113,7 @@ protected:
 	wepMap_t wepMap;
 	bool simulationMode;
 	double cummulativePredictionTime = 0;
+	std::map<resource::ComputingResource*, std::vector<std::shared_ptr<SchedulingDecision>>> scheduledTasks;
 
 protected:
 	// Hook functions for AbstractScheduler functions below to allow customisation of common functionality
@@ -121,6 +122,8 @@ protected:
 	virtual void _notifyWEPUpdate(WepMapEntry& wepe, std::set<wep::AtomicWepNode*> readyToExecute, std::unique_lock<std::mutex>& schedulerLock) {}
 	virtual void _notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {}
 
+	virtual double _getResourceEstimatedAvailableTime(resource::ComputingResource* resource);
+
 	// Convenience functions for passing a scheduling decision to the execution layer.
 	bool executeSchedulingDecision(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) noexcept;
 

include/wfr/scheduling/scheduler/heft/HEFTScheduler.h

@@ -56,8 +56,6 @@ protected:
 				fastestExecutionTimes(new prediction::ExecutionTimeResult[resourceCount]) {}
 	};
 
-	//std::map<wep::ActivityWepNode*, std::shared_ptr<OptimisticCostTableEntry>> optimisticCostTable;
-
 	std::set<wep::AtomicWepNode*> readySet;
 
 	void calcTaskRanks(wep::ActivityWepNode& node, std::vector<resource::ComputingResource*>& resources);

include/wfr/scheduling/scheduler/lookahead/LookaheadScheduler.h

@@ -0,0 +1,79 @@
+
+#pragma once
+
+
+#include <wfr/scheduling/AbstractScheduler.h>
+#include <wfr/prediction/PredictionManager.h>
+#include <wfr/common/resource/Resource.h>
+#include <wfr/common/resource/ResourceManager.h>
+#include <wfr/common/types/WfrTypes.h>
+#include <mutex>
+#include <thread>
+#include <vector>
+#include <queue>
+#include <map>
+#include <set>
+#include <iostream>
+#include <condition_variable>
+
+namespace wfr {
+
+namespace wfs {
+class AtomicActivityInstance;
+}
+namespace wep {
+class AtomicWepNode;
+class ActivityWepNode;
+class AbstractWepNode;
+}
+namespace resource {
+class ResourceManager;
+}
+namespace prediction {
+class PredictionManager;
+}
+}
+
+
+namespace wfr {
+namespace scheduling {
+
+
+class LookaheadScheduler: public scheduling::SchedulerBase {
+protected:
+	resource::ResourceManager& resourceManager;
+	prediction::PredictionManager& predictionManager;
+
+	struct TaskRankEntry {
+		double rank = 0;
+		bool finalized = false;
+
+		wfs::AtomicActivityImplementation** fastestImplementations;
+		prediction::ExecutionTimeResult* fastestExecutionTimes;
+		double averageExecutionTime = 0.0;
+
+		TaskRankEntry(wfr_size_t resourceCount) : fastestImplementations(new wfs::AtomicActivityImplementation*[resourceCount]),
+				fastestExecutionTimes(new prediction::ExecutionTimeResult[resourceCount]) {}
+	};
+
+	std::set<wep::AtomicWepNode*> readySet;
+
+	void calcTaskRanks(wep::ActivityWepNode& node, std::vector<resource::ComputingResource*>& resources);
+
+	void scheduleReadySet(WepMapEntry& wepe, std::vector<resource::ComputingResource*>& resources, std::unique_lock<std::mutex>& schedulerLock);
+
+public:
+	LookaheadScheduler(resource::ResourceManager& resourceManager, prediction::PredictionManager& predictionManager)
+			: resourceManager(resourceManager), predictionManager(predictionManager) {}
+
+	~LookaheadScheduler() {}
+
+	virtual void _notifyWEPUpdate(SchedulerBase::WepMapEntry& wepe, std::set<wep::AtomicWepNode*> readyToExecute, std::unique_lock<std::mutex>& schedulerLock) override;
+	virtual void _notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) override;
+	virtual void _unregisterWEP(WepMapEntry& wepe, std::unique_lock<std::mutex>& schedulerLock) override;
+};
+
+} /* namespace scheduling */
+} /* namespace wfr */
+
+

include/wfr/scheduling/scheduler/minmin/MinMinScheduler.h

@@ -25,13 +25,9 @@ protected:
 	resource::ResourceManager& resourceManager;
 	prediction::PredictionManager& predictionManager;
 
-	std::map<resource::ComputingResource*, std::vector<std::shared_ptr<SchedulingDecision>>> scheduledTasks;
-
 	typedef std::map<resource::ComputingResourceType*, std::pair<wfs::AtomicActivityImplementation*, prediction::ExecutionTimeResult>> ImplementationCacheInnerMap;
 	std::map<wfs::AtomicActivityType*, ImplementationCacheInnerMap> implementationCache;
 
-	double _getResourceEstimatedAvailableTime(resource::ComputingResource* resource);
-
 	typedef std::tuple<resource::ComputingResource*, wfs::AtomicActivityImplementation*, double, prediction::ExecutionTimeResult> ECTEntry;
 	virtual std::pair<wep::AtomicWepNode*, ECTEntry> _getNextTaskToSchedule(std::map<wep::AtomicWepNode*, ECTEntry>& estimatedTaskCompletionTimes);
 

include/wfr/scheduling/scheduler/sufferage/SufferageScheduler.h

@@ -25,13 +25,9 @@ protected:
 	resource::ResourceManager& resourceManager;
 	prediction::PredictionManager& predictionManager;
 
-	std::map<resource::ComputingResource*, std::vector<std::shared_ptr<SchedulingDecision>>> scheduledTasks;
-
 	typedef std::map<resource::ComputingResourceType*, std::pair<wfs::AtomicActivityImplementation*, prediction::ExecutionTimeResult>> ImplementationCacheInnerMap;
 	std::map<wfs::AtomicActivityType*, ImplementationCacheInnerMap> implementationCache;
 
-	double _getResourceEstimatedAvailableTime(resource::ComputingResource* resource);
-
 	typedef std::tuple<resource::ComputingResource*, wfs::AtomicActivityImplementation*, double, prediction::ExecutionTimeResult> ECTEntry;
 	std::pair<wep::AtomicWepNode*, ECTEntry> _getNextTaskToSchedule(std::map<wep::AtomicWepNode*, ECTEntry>& estimatedTaskCompletionTimes);
 

src/scheduling/AbstractScheduler.cpp

@@ -67,6 +67,7 @@ void SchedulerBase::notifyWEPUpdate(wep::WorkflowExecutionPlan& wep, std::set<we
 
 bool SchedulerBase::executeSchedulingDecision(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) noexcept {
 	wepe.decisions.insert(sd);
+	scheduledTasks[sd->resource].push_back(sd);
 	schedulerLock.unlock();
 	sd->activityInstance->setSchedulingDecision(sd);
 	if (sd->activityInstance->activityType() == wfs::ActivityType::Atomic) {
@@ -92,6 +93,13 @@ void SchedulerBase::notifySchedulingDecisionStatusUpdate(std::shared_ptr<Schedul
 		std::unique_lock<std::mutex> objLock(schedulerMutex);
 		auto wepe = wepMap.find(sd->wep);
 		if (wepe != wepMap.end()) {
+			auto& innerMap = scheduledTasks[sd->resource];
+			for (auto i = innerMap.begin(); i != innerMap.end(); i++) {
+				if (*i == sd) {
+					innerMap.erase(i);
+					break;
+				}
+			}
 			_notifySchedulingDecisionStatusUpdate(wepe->second, sd, objLock);
 			// Notify enactment engine
 			auto ee = wepe->second.engine;
@@ -102,6 +110,36 @@ void SchedulerBase::notifySchedulingDecisionStatusUpdate(std::shared_ptr<Schedul
 	}
 }
 
+double SchedulerBase::_getResourceEstimatedAvailableTime(resource::ComputingResource* resource) {
+	if (resource->getFreeSlotCount() > 0) {
+		return 0.0;
+	} else {
+		// Calculating the estimated available time for resources with more than 1 slot is not trivial
+		// Here we are employing a heuristic that partitions the scheduled tasks into chunks the size of the maximal slot count,
+		// takes the minimum time of each chunk and adds them together.
+		unsigned i = 0;
+		double eat = 0;
+		double minTime = -1;
+		auto& tasks = scheduledTasks[resource];
+		for (auto t : tasks) {
+			i++;
+			if (minTime < 0) {
+				minTime = t->getPrediction().getExecutionTime().getValue();
+			} else {
+				if (i > resource->getMaxSlotCount()) {
+					eat += minTime;
+					i = 0;
+					minTime = t->getPrediction().getExecutionTime().getValue();
+				} else {
+					if (t->getPrediction().getExecutionTime().getValue() < minTime) {
+						minTime = t->getPrediction().getExecutionTime().getValue();
+					}
+				}
+			}
+		}
+		return eat;
+	}
+}
 
 } /* namespace scheduling */
 } /* namespace wfr */

src/scheduling/SchedulerManager.cpp

@@ -16,6 +16,7 @@
 #include <wfr/scheduling/scheduler/maxmin/MaxMinScheduler.h>
 #include <wfr/scheduling/scheduler/sufferage/SufferageScheduler.h>
 #include <wfr/scheduling/scheduler/peft/PEFTScheduler.h>
+#include <wfr/scheduling/scheduler/lookahead/LookaheadScheduler.h>
 
 namespace wfr {
 namespace scheduling {
@@ -78,6 +79,9 @@ SchedulerManager::SchedulerManager(std::string defaultScheduler) : defaultSchedu
     schedulerFactories.insert(factoryMap_t::value_type("heft", []()->AbstractScheduler* {
     	return new HEFTScheduler(resource::ResourceManager::getInstance(), prediction::PredictionManager::getInstance());
     }));
+    schedulerFactories.insert(factoryMap_t::value_type("lookahead", []()->AbstractScheduler* {
+    	return new LookaheadScheduler(resource::ResourceManager::getInstance(), prediction::PredictionManager::getInstance());
+    }));
     schedulerFactories.insert(factoryMap_t::value_type("random", []()->AbstractScheduler* {
     	return new RandomScheduler(resource::ResourceManager::getInstance(), prediction::PredictionManager::getInstance());
     }));

src/scheduling/cmake.inc

@@ -10,4 +10,5 @@ set(wfr_cpp_files "${wfr_cpp_files}"
 	src/scheduling/scheduler/maxmin/MaxMinScheduler.cpp
 	src/scheduling/scheduler/sufferage/SufferageScheduler.cpp
 	src/scheduling/scheduler/peft/PEFTScheduler.cpp
+	src/scheduling/scheduler/lookahead/LookaheadScheduler.cpp
 )

src/scheduling/scheduler/heft/HEFTScheduler.cpp

@@ -29,6 +29,7 @@ namespace wfr {
 namespace scheduling {
 
 
+
 void HEFTScheduler::calcTaskRanks(wep::ActivityWepNode& node, std::vector<resource::ComputingResource*>& resources) {
 	/*std::cout << "calcTaskRanks: " << node.activity.baseActivity.baseTemplate.activityName << " (" << node.activity.instanceID << ")"
 			<< " [" << print::toString(node.activity.baseActivity.activityType()) << "]"
@@ -156,11 +157,6 @@ void HEFTScheduler::_notifyWEPUpdate(SchedulerBase::WepMapEntry& wepe, std::set<
 	scheduleReadySet(wepe, resources, schedulerLock);
 }
 
-void HEFTScheduler::_notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {
-	//auto resources = resourceManager.getComputingResources();
-	//scheduleReadySet(wepe, resources, schedulerLock);
-}
-
 
 void HEFTScheduler::scheduleReadySet(WepMapEntry& wepe, std::vector<resource::ComputingResource*>& resources, std::unique_lock<std::mutex>& schedulerLock) {
 	struct _schedulingPriorityQueueComparison {
@@ -193,9 +189,12 @@ void HEFTScheduler::scheduleReadySet(WepMapEntry& wepe, std::vector<resource::Co
 		prediction::ExecutionTimeResult fastestPred;
 		wfs::AtomicActivityImplementation* fastestImpl = nullptr;
 		resource::ComputingResource* fastestResource = nullptr;
+		double earliestEstimatedFinishTime = -1;
 		for (auto res : resources) {
-			if (entry->fastestImplementations[ri] && res->getFreeSlotCount() > 0) {
-				if (!fastestPred.isValid() || entry->fastestExecutionTimes[ri].executionTime.getValue() < fastestPred.executionTime.getValue()) {
+			if (entry->fastestImplementations[ri]) {
+				auto estimatedFinishTime = _getResourceEstimatedAvailableTime(res) + entry->fastestExecutionTimes[ri].executionTime.getValue();
+				if (earliestEstimatedFinishTime < 0.0 || estimatedFinishTime < earliestEstimatedFinishTime) {
+					earliestEstimatedFinishTime = estimatedFinishTime;
 					fastestImpl = entry->fastestImplementations[ri];
 					fastestPred = entry->fastestExecutionTimes[ri];
 					fastestResource = res;
@@ -222,6 +221,11 @@ void HEFTScheduler::scheduleReadySet(WepMapEntry& wepe, std::vector<resource::Co
 	}
 }
 
+void HEFTScheduler::_notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {
+	//auto resources = resourceManager.getComputingResources();
+	//scheduleReadySet(wepe, resources, schedulerLock);
+}
+
 
 void HEFTScheduler::_unregisterWEP(WepMapEntry& wepe, std::unique_lock<std::mutex>& schedulerLock) {
 	/*std::cout << "Task Ranks: " << std::endl;

src/scheduling/scheduler/lookahead/LookaheadScheduler.cpp

@@ -0,0 +1,319 @@
+
+
+#include <wfr/prediction/PredictionManager.h>
+#include <wfr/common/resource/ResourceManager.h>
+#include <wfr/common/wep/WorkflowExecutionPlan.h>
+#include <wfr/common/wep/AbstractWepNode.h>
+#include <wfr/common/wep/activities/AtomicWepNode.h>
+#include <wfr/common/wep/ActivityWepNode.h>
+#include <wfr/common/wfs/Activity.h>
+#include <wfr/common/wfs/ActivityInstance.h>
+#include <wfr/common/wfs/instances/AtomicActivityInstance.h>
+#include <wfr/common/wfs/AtomicActivityImplementation.h>
+#include <wfr/common/wfs/templates/AtomicActivityTemplate.h>
+#include <wfr/enactment/EnactmentEngine.h>
+#include <wfr/common/scheduling/SchedulingDecision.h>
+#include <wfr/execution/ExecutionManager.h>
+#include <wfr/wep/utils/WepSearch.h>
+#include <wfr/common/utils/print.h>
+#include <iostream>
+#include <set>
+#include <boost/format.hpp>
+#include <wfr/scheduling/scheduler/lookahead/LookaheadScheduler.h>
+#include <queue>
+#include <memory>
+#include <cstring>
+
+
+namespace wfr {
+namespace scheduling {
+
+
+
+void LookaheadScheduler::calcTaskRanks(wep::ActivityWepNode& node, std::vector<resource::ComputingResource*>& resources) {
+	/*std::cout << "calcTaskRanks: " << node.activity.baseActivity.baseTemplate.activityName << " (" << node.activity.instanceID << ")"
+			<< " [" << print::toString(node.activity.baseActivity.activityType()) << "]"
+			<< " [" << (int)node.nodeType << "]" << std::endl;*/
+
+	auto entry = (TaskRankEntry*)node.getUserData().get();
+	if (!entry) {
+		entry = new TaskRankEntry(resources.size());
+		if (node.nodeType == wep::WepNodeType::Atomic) {
+			// get fastest implementation for each resource
+			unsigned ri = 0;
+			double sumExecutionTimes = 0.0;
+			unsigned sumExecutionTimeCount = 0;
+			for (auto res : resources) {
+				prediction::ExecutionTimeResult fastestPred;
+				wfs::AtomicActivityImplementation* fastestImpl = nullptr;
+				for (auto impl : node.activity.baseActivity.baseTemplate.as<wfs::AtomicActivityTemplate>().atomicActivityType->getImplementations()) {
+					auto pred = predictionManager.predictExecutionTime(node.activity, *impl, res->resourceType, 1);
+					if (pred.isValid()) {
+						if (!fastestPred.isValid() || pred < fastestPred) {
+							fastestPred = pred;
+							fastestImpl = impl;
+						}
+					}
+				}
+				entry->fastestImplementations[ri] = fastestImpl;
+				entry->fastestExecutionTimes[ri] = fastestPred;
+				if (fastestPred.isValid()) {
+					sumExecutionTimeCount++;
+					sumExecutionTimes += fastestPred.executionTime.getValue();
+				}
+				ri++;
+			}
+			entry->averageExecutionTime = sumExecutionTimes / (double)sumExecutionTimeCount;
+		}
+		node.setUserData(std::shared_ptr<void>(entry));
+		if (node.nodeType == wep::WepNodeType::Atomic) {
+			node.activity.setUserData(std::shared_ptr<void>(entry));
+		}
+	}
+	if (!entry->finalized) {
+		auto successors = node.getSuccessors();
+		if (successors.size() == 0) {
+			// exit task
+			//std::cout << "\tNo successors => exit task: " << entry->averageExecutionTime << std::endl;
+			entry->rank = entry->averageExecutionTime;
+			entry->finalized = true;
+		} else {
+			bool succsFinalized = true;
+			double maxSuccRank = 0.0;
+			for (auto s : successors) {
+				auto& succ = s->as<wep::ActivityWepNode>();
+				/*std::cout << "\tSuccessor: " << succ.activity.baseActivity.baseTemplate.activityName << " (" << succ.activity.instanceID << ")"
+						<< " [" << print::toString(succ.activity.baseActivity.activityType()) << "]"
+						<< "[" << (int)succ.nodeType << "]" << std::endl;*/
+				auto succEntry = (TaskRankEntry*)succ.getUserData().get();
+				if (!succEntry || !succEntry->finalized) {
+					// recursively calculate ranks
+					//std::cout << "recursive call start" << std::endl;
+					calcTaskRanks(succ, resources);
+					//std::cout << "recursive call end" << std::endl;
+					if (!succEntry) {
+						succEntry = (TaskRankEntry*)succ.getUserData().get();
+					}
+					succsFinalized = succsFinalized && succEntry->finalized;
+				}
+				// Get average communication time
+				double averaveCommTime = 0.0;
+				if (node.nodeType == wep::WepNodeType::Atomic && succ.nodeType == wep::WepNodeType::Atomic) {
+					double sumCommTime = 0.0;
+					unsigned sumCommTimeCount = 0;
+					for (auto res1 : resources) {
+						for (auto res2 : resources) {
+							if (res1 != res2) {
+								auto pred = predictionManager.predictCommunicationTime(node.activity, *res1, succ.activity, *res2);
+								if (pred.isValid) {
+									sumCommTime += pred.communicationTime.getValue();
+									sumCommTimeCount++;
+								}
+							}
+						}
+					}
+					averaveCommTime = sumCommTime / (double)sumCommTimeCount;
+				}
+				auto succRank = averaveCommTime + succEntry->rank;
+				if (succRank > maxSuccRank) {
+					maxSuccRank = succRank;
+				}
+			}
+			if (node.nodeType == wep::WepNodeType::Atomic) {
+				/*std::cout << "AverageExecTime: " << node.activity.baseActivity.baseTemplate.activityName << " (" << node.activity.instanceID << ")"
+						<< " [" << print::toString(node.activity.baseActivity.activityType()) << "]"
+						<< " [" << (int)node.nodeType << "]: " << entry->averageExecutionTime << std::endl;*/
+				entry->rank = entry->averageExecutionTime + maxSuccRank;
+			} else {
+				entry->rank = maxSuccRank;
+			}
+			/*std::cout << "Rank: " << node.activity.baseActivity.baseTemplate.activityName << " (" << node.activity.instanceID << ")"
+					<< " [" << print::toString(node.activity.baseActivity.activityType()) << "]"
+					<< " [" << (int)node.nodeType << "]: " << entry->rank << std::endl;*/
+			if (succsFinalized) {
+				if (node.nodeType == wep::WepNodeType::CompositeStart || node.nodeType == wep::WepNodeType::IterationStart) {
+					if (node.getLastKnownInstanceStatus() >= wfs::ActivityInstanceStatus::ReadyForExecution) {
+						entry->finalized = true;
+					}
+				} else {
+					entry->finalized = true;
+				}
+				/*if (entry->finalized) {
+					std::cout << "Finalizing: " << node.activity.baseActivity.baseTemplate.activityName << " (" << node.activity.instanceID << ")"
+							<< " [" << print::toString(node.activity.baseActivity.activityType()) << "]"
+							<< " [" << (int)node.nodeType << "]" << std::endl;
+				}*/
+			}
+		}
+	}
+}
+
+
+void LookaheadScheduler::_notifyWEPUpdate(SchedulerBase::WepMapEntry& wepe, std::set<wep::AtomicWepNode*> readyToExecute, std::unique_lock<std::mutex>& schedulerLock) {
+	auto resourceTypes = resourceManager.getComputingResourceTypes();
+	auto resources = resourceManager.getComputingResources();
+
+	calcTaskRanks(wepe.wep->getStartNode()->as<wep::ActivityWepNode>(), resources);
+
+	readySet.insert(readyToExecute.begin(), readyToExecute.end());
+
+	scheduleReadySet(wepe, resources, schedulerLock);
+}
+
+
+void LookaheadScheduler::scheduleReadySet(WepMapEntry& wepe, std::vector<resource::ComputingResource*>& resources, std::unique_lock<std::mutex>& schedulerLock) {
+	struct _schedulingPriorityQueueComparison {
+		bool operator()(wep::AtomicWepNode* e1, wep::AtomicWepNode* e2) {
+			auto entry1 = (TaskRankEntry*)e1->getUserData().get();
+			auto entry2 = (TaskRankEntry*)e2->getUserData().get();
+			if (entry1 && !entry2) {
+				return false;
+			} else if (!entry1 && entry2) {
+				return true;
+			} else if (entry1 && entry2) {
+				return entry1->rank < entry2->rank;
+			} else {
+				return false;
+			}
+		}
+	};
+	std::priority_queue<wep::AtomicWepNode*, std::vector<wep::AtomicWepNode*>, _schedulingPriorityQueueComparison> schedulingPriorityQueue;
+	// Put elements from ready set into priority queue thereby sorting them by rank
+	for (auto n : readySet) {
+		schedulingPriorityQueue.push(n);
+	}
+
+	while (!schedulingPriorityQueue.empty()) {
+		auto task = schedulingPriorityQueue.top();
+		schedulingPriorityQueue.pop();
+		auto entry = (TaskRankEntry*)task->getUserData().get();
+		int ri = 0;
+
+		prediction::ExecutionTimeResult fastestPred;
+		wfs::AtomicActivityImplementation* fastestImpl = nullptr;
+		resource::ComputingResource* fastestResource = nullptr;
+		double earliestEstimatedFinishTime = -1;
+		double minSuccEFT = -1;
+		auto succs = task->activity.getSuccessors();
+		for (auto res : resources) {
+			if (entry->fastestImplementations[ri]) {
+				auto estimatedFinishTime = _getResourceEstimatedAvailableTime(res) + entry->fastestExecutionTimes[ri].executionTime.getValue();
+
+				auto maxSuccEFT = -1;
+				if (succs.size() > 0) {
+					// do lookahead
+					struct _succSchedulingQueueComparison {
+						bool operator()(wfs::ActivityInstance* e1, wfs::ActivityInstance* e2) {
+							auto entry1 = (TaskRankEntry*)e1->getUserData().get();
+							auto entry2 = (TaskRankEntry*)e2->getUserData().get();
+							if (entry1 && !entry2) {
+								return false;
+							} else if (!entry1 && entry2) {
+								return true;
+							} else if (entry1 && entry2) {
+								return entry1->rank < entry2->rank;
+							} else {
+								return false;
+							}
+						}
+					};
+					std::priority_queue<wfs::ActivityInstance*, std::vector<wfs::ActivityInstance*>, _succSchedulingQueueComparison> succSchedulingQueue;
+					std::map<resource::ComputingResource*, double> resourceEATMap;
+					resourceEATMap[res] = estimatedFinishTime;
+					for (auto succ : succs) {
+						if (succ->activityType() == wfs::ActivityType::Atomic) {
+							succSchedulingQueue.push(succ);
+						}
+					}
+					while (!succSchedulingQueue.empty()) {
+						auto succ = succSchedulingQueue.top();
+						succSchedulingQueue.pop();
+						auto succEntry = (TaskRankEntry*)succ->getUserData().get();
+						unsigned ri2 = 0;
+						unsigned minEFT = -1;
+						resource::ComputingResource* minEFTResource = nullptr;
+						for (auto res2 : resources) {
+							double succEFT = -1;
+							if (entry->fastestImplementations[ri2]) {
+								succEFT = resourceEATMap[res2] + succEntry->fastestExecutionTimes[ri2].executionTime.getValue();
+							}
+							if (succEFT > 0 && (minEFT < 0 || succEFT < minEFT)) {
+								minEFT = succEFT;
+								minEFTResource = res2;
+							}
+						}
+						if (minEFT > 0) {
+							resourceEATMap[minEFTResource] = minEFT;
+						}
+					}
+					for (auto e : resourceEATMap) {
+						if (maxSuccEFT < 0 || e.second > maxSuccEFT) {
+							maxSuccEFT = e.second;
+						}
+					}
+					if (minSuccEFT < 0 || maxSuccEFT < minSuccEFT) {
+						minSuccEFT = maxSuccEFT;
+						earliestEstimatedFinishTime = estimatedFinishTime;
+						fastestImpl = entry->fastestImplementations[ri];
+						fastestPred = entry->fastestExecutionTimes[ri];
+						fastestResource = res;
+					}
+				// no successors
+				} else if (earliestEstimatedFinishTime < 0.0 || estimatedFinishTime < earliestEstimatedFinishTime) {
+					earliestEstimatedFinishTime = estimatedFinishTime;
+					fastestImpl = entry->fastestImplementations[ri];
+					fastestPred = entry->fastestExecutionTimes[ri];
+					fastestResource = res;
+				}
+			}
+			ri++;
+		}
+		if (fastestResource) {
+
+			/*auto entry = (TaskRankEntry*)task->getUserData().get();
+			std::cout << task->activity.baseActivity.baseTemplate.activityName << "[" << task->activity.instanceID << "]: "
+					<< entry->rank << std::endl;
+			std::cout << "\tFastest Resource: " << fastestResource->resourceIdentifier << ": prediction = " << fastestPred.getExecutionTime().getValue() << std::endl;*/
+
+			auto reservation = resourceManager.reserveComputingResource(fastestResource, 1, true);
+			if (reservation) {
+				std::shared_ptr<SchedulingDecision> sd = std::make_shared<SchedulingDecision>(&task->activity, fastestImpl, wepe.wep, reservation);
+				sd->setPrediction(fastestPred);
+				task->activity.setInstanceStatus(wfs::ActivityInstanceStatus::Scheduled);
+				executeSchedulingDecision(wepe, sd, schedulerLock);
+				readySet.erase(task);
+			}
+		}
+	}
+}
+
+void LookaheadScheduler::_notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {
+	//auto resources = resourceManager.getComputingResources();
+	//scheduleReadySet(wepe, resources, schedulerLock);
+}
+
+
+void LookaheadScheduler::_unregisterWEP(WepMapEntry& wepe, std::unique_lock<std::mutex>& schedulerLock) {
+	/*std::cout << "Task Ranks: " << std::endl;
+	std::set<wep::AbstractWepNode*> visitedNodes;
+	auto visitFunc = [&](wep::AbstractWepNode* node) -> bool {
+		if (visitedNodes.find(node) == visitedNodes.end()) {
+			auto entry = (TaskRankEntry*)node->getUserData().get();
+			if (entry) {
+				std::cout << "\t" << node->as<wep::ActivityWepNode>().activity.baseActivity.baseTemplate.activityName
+						<< "[" << node->as<wep::ActivityWepNode>().activity.instanceID << "]: " << entry->rank << std::endl;
+			} else {
+				std::cout << "\t" << node->as<wep::ActivityWepNode>().activity.baseActivity.baseTemplate.activityName
+						<< "[" << node->as<wep::ActivityWepNode>().activity.instanceID << "]: No Entry" << std::endl;
+			}
+			visitedNodes.insert(node);
+		}
+		return true;
+	};
+	wfr::utils::wep::wepBreadthFirstSearch(wepe.wep->getStartNode(), visitFunc);*/
+}
+
+} /* namespace scheduler */
+} /* namespace wfr */
+
+

src/scheduling/scheduler/minmin/MinMinScheduler.cpp

@@ -24,39 +24,6 @@ namespace scheduling {
 
 
 
-
-double MinMinScheduler::_getResourceEstimatedAvailableTime(resource::ComputingResource* resource) {
-	if (resource->getFreeSlotCount() > 0) {
-		return 0.0;
-	} else {
-		// Calculating the estimated available time for resources with more than 1 slot is not trivial
-		// Here we are employing a heuristic that partitions the scheduled tasks into chunks the size of the maximal slot count,
-		// takes the minimum time of each chunk and adds them together.
-		unsigned i = 0;
-		double eat = 0;
-		double minTime = -1;
-		auto& tasks = scheduledTasks[resource];
-		for (auto t : tasks) {
-			i++;
-			if (minTime < 0) {
-				minTime = t->getPrediction().getExecutionTime().getValue();
-			} else {
-				if (i > resource->getMaxSlotCount()) {
-					eat += minTime;
-					i = 0;
-					minTime = t->getPrediction().getExecutionTime().getValue();
-				} else {
-					if (t->getPrediction().getExecutionTime().getValue() < minTime) {
-						minTime = t->getPrediction().getExecutionTime().getValue();
-					}
-				}
-			}
-		}
-		return eat;
-	}
-}
-
-
 std::pair<wep::AtomicWepNode*, MinMinScheduler::ECTEntry> MinMinScheduler::_getNextTaskToSchedule(std::map<wep::AtomicWepNode*, ECTEntry>& estimatedTaskCompletionTimes) {
 	wep::AtomicWepNode* selectedNode = nullptr;
 	ECTEntry selectedEntry;
@@ -143,22 +110,13 @@ void MinMinScheduler::_notifyWEPUpdate(SchedulerBase::WepMapEntry& wepe, std::se
 			auto sd = std::make_shared<SchedulingDecision>(&selectedTask.first->activity, std::get<1>(selectedTask.second), wepe.wep, reservation);
 			sd->setPrediction(std::get<3>(selectedTask.second));
 			selectedTask.first->activity.setInstanceStatus(wfs::ActivityInstanceStatus::Scheduled);
-			scheduledTasks[sd->resource].push_back(sd);
 			executeSchedulingDecision(wepe, sd, schedulerLock);
 			readyToExecute.erase(selectedTask.first);
 		}
 	}
 }
 
-void MinMinScheduler::_notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {
-	auto& innerMap = scheduledTasks[sd->resource];
-	for (auto i = innerMap.begin(); i != innerMap.end(); i++) {
-		if (*i == sd) {
-			innerMap.erase(i);
-			break;
-		}
-	}
-}
+void MinMinScheduler::_notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {}
 
 } /* namespace scheduling */
 } /* namespace wfr */

src/scheduling/scheduler/peft/PEFTScheduler.cpp

@@ -29,6 +29,7 @@ namespace wfr {
 namespace scheduling {
 
 
+
 void PEFTScheduler::calcOptimisticCosts(wep::ActivityWepNode& node, std::vector<resource::ComputingResource*>& resources) {
 	/*std::cout << "calcOptimisticCosts: " << node.activity.baseActivity.baseTemplate.activityName << " (" << node.activity.instanceID << ")"
 			<< " [" << print::toString(node.activity.baseActivity.activityType()) << "]"
@@ -157,11 +158,6 @@ void PEFTScheduler::_notifyWEPUpdate(SchedulerBase::WepMapEntry& wepe, std::set<
 	scheduleReadySet(wepe, resources, schedulerLock);
 }
 
-void PEFTScheduler::_notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {
-	//auto resources = resourceManager.getComputingResources();
-	//scheduleReadySet(wepe, resources, schedulerLock);
-}
-
 
 void PEFTScheduler::scheduleReadySet(WepMapEntry& wepe, std::vector<resource::ComputingResource*>& resources, std::unique_lock<std::mutex>& schedulerLock) {
 	struct _schedulingPriorityQueueComparison {
@@ -194,9 +190,12 @@ void PEFTScheduler::scheduleReadySet(WepMapEntry& wepe, std::vector<resource::Co
 		prediction::ExecutionTimeResult fastestPred;
 		wfs::AtomicActivityImplementation* fastestImpl = nullptr;
 		resource::ComputingResource* fastestResource = nullptr;
+		double earliestEstimatedFinishTime = -1;
 		for (auto res : resources) {
-			if (entry->fastestImplementations[ri] && res->getFreeSlotCount() > 0) {
-				if (!fastestPred.isValid() || entry->fastestExecutionTimes[ri].executionTime.getValue() < fastestPred.executionTime.getValue()) {
+			if (entry->fastestImplementations[ri]) {
+				auto estimatedFinishTime = _getResourceEstimatedAvailableTime(res) + entry->fastestExecutionTimes[ri].executionTime.getValue();
+				if (earliestEstimatedFinishTime < 0.0 || estimatedFinishTime < earliestEstimatedFinishTime) {
+					earliestEstimatedFinishTime = estimatedFinishTime;
 					fastestImpl = entry->fastestImplementations[ri];
 					fastestPred = entry->fastestExecutionTimes[ri];
 					fastestResource = res;
@@ -217,6 +216,11 @@ void PEFTScheduler::scheduleReadySet(WepMapEntry& wepe, std::vector<resource::Co
 	}
 }
 
+void PEFTScheduler::_notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {
+	//auto resources = resourceManager.getComputingResources();
+	//scheduleReadySet(wepe, resources, schedulerLock);
+}
+
 
 
 } /* namespace scheduler */

src/scheduling/scheduler/sufferage/SufferageScheduler.cpp

@@ -24,39 +24,6 @@ namespace scheduling {
 
 
 
-
-double SufferageScheduler::_getResourceEstimatedAvailableTime(resource::ComputingResource* resource) {
-	if (resource->getFreeSlotCount() > 0) {
-		return 0.0;
-	} else {
-		// Calculating the estimated available time for resources with more than 1 slot is not trivial
-		// Here we are employing a heuristic that partitions the scheduled tasks into chunks the size of the maximal slot count,
-		// takes the minimum time of each chunk and adds them together.
-		unsigned i = 0;
-		double eat = 0;
-		double minTime = -1;
-		auto& tasks = scheduledTasks[resource];
-		for (auto t : tasks) {
-			i++;
-			if (minTime < 0) {
-				minTime = t->getPrediction().getExecutionTime().getValue();
-			} else {
-				if (i > resource->getMaxSlotCount()) {
-					eat += minTime;
-					i = 0;
-					minTime = t->getPrediction().getExecutionTime().getValue();
-				} else {
-					if (t->getPrediction().getExecutionTime().getValue() < minTime) {
-						minTime = t->getPrediction().getExecutionTime().getValue();
-					}
-				}
-			}
-		}
-		return eat;
-	}
-}
-
-
 std::pair<wep::AtomicWepNode*, SufferageScheduler::ECTEntry> SufferageScheduler::_getNextTaskToSchedule(std::map<wep::AtomicWepNode*, ECTEntry>& estimatedTaskCompletionTimes) {
 	wep::AtomicWepNode* selectedNode = nullptr;
 	ECTEntry selectedEntry;
@@ -155,22 +122,13 @@ void SufferageScheduler::_notifyWEPUpdate(SchedulerBase::WepMapEntry& wepe, std:
 			auto sd = std::make_shared<SchedulingDecision>(&selectedTask.first->activity, std::get<1>(selectedTask.second), wepe.wep, reservation);
 			sd->setPrediction(std::get<3>(selectedTask.second));
 			selectedTask.first->activity.setInstanceStatus(wfs::ActivityInstanceStatus::Scheduled);
-			scheduledTasks[sd->resource].push_back(sd);
 			executeSchedulingDecision(wepe, sd, schedulerLock);
 			readyToExecute.erase(selectedTask.first);
 		}
 	}
 }
 
-void SufferageScheduler::_notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {
-	auto& innerMap = scheduledTasks[sd->resource];
-	for (auto i = innerMap.begin(); i != innerMap.end(); i++) {
-		if (*i == sd) {
-			innerMap.erase(i);
-			break;
-		}
-	}
-}
+void SufferageScheduler::_notifySchedulingDecisionStatusUpdate(WepMapEntry& wepe, std::shared_ptr<SchedulingDecision> sd, std::unique_lock<std::mutex>& schedulerLock) {}
 
 } /* namespace scheduling */
 } /* namespace wfr */