ptolemy.actor.lib.aspect

Class FixedPriorityScheduler

java.lang.Object

ptolemy.kernel.util.NamedObj

ptolemy.kernel.InstantiableNamedObj

ptolemy.kernel.Entity<T>

ptolemy.kernel.ComponentEntity<T>

ptolemy.actor.AtomicActor<TypedIOPort>

ptolemy.actor.TypedAtomicActor

ptolemy.actor.lib.aspect.AtomicExecutionAspect

ptolemy.actor.lib.aspect.FixedPriorityScheduler

All Implemented Interfaces:

java.lang.Cloneable, Actor, ActorExecutionAspect, Executable, FiringsRecordable, Initializable, TypedActor, Changeable, Debuggable, DebugListener, Decorator, Derivable, Instantiable, ModelErrorHandler, MoMLExportable, Moveable, Nameable

Direct Known Subclasses:

EDFScheduler

public class FixedPriorityScheduler
extends AtomicExecutionAspect

This is a fixed priority scheduler resource manager on a single processor or core. This attribute decorates actors in the model at the same and lower levels of the hierarchy, including those inside opaque composite actors. It decorates them with the following parameters:

• enable: If true, then the decorated actor will use this resource. This is a boolean that defaults to false.
• executionTime: Specifies the execution time of the decorated actor. This means the time that the decorated actor occupies the processor or core when it fires. This is a double that defaults to 0.0.
• priority: An integer where a lower number indicates a higher priority. E.g., priority 1 means higher priority than priority 2. Priority 0 means higher priority than any positive number. Priority -1 means higher priority than any non-negative number.

For usage and supported directors, see ActorExecutionAspect. When using this ExecutionAspect in the Ptides domain, the platform time in Ptides will be used to schedule execution times. When the Ptides director requests that an actor fire, if this resource is free, it will immediately schedule it. Otherwise, it will queue it to be executed when the resource becomes free. When the resource becomes free, the actor with the highest priority (the lower priority number) will be chosen from the queue to be executed. If two actors have the same highest priority, then they will be executed in FIFO order.

Since:

Ptolemy II 10.0

Version:

$Id$

Author:

Patricia Derler, Edward A. Lee

Pt.AcceptedRating:

Red (derler)

Pt.ProposedRating:

Yellow (eal)

Nested Class Summary

Nested classes/interfaces inherited from class ptolemy.kernel.Entity

Entity.ContainedObjectsIterator

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.Stack<NamedObj>	_currentlyExecuting Stack of currently executing actors.
static int	LOWEST_PRIORITY Lowest task priority.
Parameter	preemptive Parameter to configure whether a preemptive or non-preemptive scheduling strategy should be used.

Fields inherited from class ptolemy.actor.lib.aspect.AtomicExecutionAspect

_actors, _executionAspectListeners, _lastActorFinished, _lastActorThatFinished, _lastTimeScheduled, _remainingTimes

Fields inherited from class ptolemy.actor.TypedAtomicActor

_typesValid

Fields inherited from class ptolemy.actor.AtomicActor

_actorFiringListeners, _initializables, _notifyingActorFiring, _stopRequested

Fields inherited from class ptolemy.kernel.util.NamedObj

_changeListeners, _changeLock, _changeRequests, _debugging, _debugListeners, _deferChangeRequests, _elementName, _isPersistent, _verbose, _workspace, ATTRIBUTES, CLASSNAME, COMPLETE, CONTENTS, DEEP, FULLNAME, LINKS

Fields inherited from interface ptolemy.actor.Executable

COMPLETED, NOT_READY, STOP_ITERATING

Constructor Summary

Constructors

Constructor and Description
FixedPriorityScheduler(CompositeEntity container, java.lang.String name) Create a new actor in the specified container with the specified name.

Method Summary

Modifier and Type	Method and Description
protected double	_getPriority(NamedObj actor) Get the priority of the actor.
void	attributeChanged(Attribute attribute) If the attribute is preemptive then change the scheduling algorithm to be preemptive or non-preemptive.
java.lang.Object	clone(Workspace workspace) Clone the actor into the specified workspace.
DecoratorAttributes	createDecoratorAttributes(NamedObj target) Return the decorated attributes for the target NamedObj.
void	initialize() Initialize local variables.
Time	schedule(NamedObj actor, Time currentPlatformTime, Time deadline, Time executionTime) Schedule a new actor for execution and return the next time this aspect has to perform a reschedule.
Time	schedule(Time environmentTime) Perform rescheduling actions when no new actor requests to be scheduled.

Methods inherited from class ptolemy.actor.lib.aspect.AtomicExecutionAspect

_getDeadline, addExecutingListener, decoratedObjects, fire, getExecutionTime, getRemainingTime, getTime, initializeDecoratedActors, isGlobalDecorator, isWaitingForResource, lastActorFinished, lastScheduledActorFinished, notifyExecutionListeners, removeExecutionListener, setContainer, wrapup

Methods inherited from class ptolemy.actor.TypedAtomicActor

_containedTypeConstraints, _customTypeConstraints, _defaultTypeConstraints, _fireAt, _fireAt, attributeTypeChanged, clone, isBackwardTypeInferenceEnabled, newPort, typeConstraintList, typeConstraints

Methods inherited from class ptolemy.actor.AtomicActor

_actorFiring, _actorFiring, _declareDelayDependency, addActorFiringListener, addInitializable, connectionsChanged, createReceivers, declareDelayDependency, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, isFireFunctional, isStrict, iterate, newReceiver, outputPortList, postfire, prefire, preinitialize, pruneDependencies, recordFiring, removeActorFiringListener, removeDependency, removeInitializable, stop, stopFire, terminate

Methods inherited from class ptolemy.kernel.ComponentEntity

_adjustDeferrals, _checkContainer, _getContainedObject, _propagateExistence, getContainer, instantiate, isAtomic, isOpaque, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, propagateExistence, setName

Methods inherited from class ptolemy.kernel.Entity

_addPort, _description, _exportMoMLContents, _removePort, _validateSettables, connectedPortList, connectedPorts, containedObjectsIterator, getAttribute, getPort, getPorts, linkedRelationList, linkedRelations, portList, removeAllPorts, setClassDefinition, uniqueName

Methods inherited from class ptolemy.kernel.InstantiableNamedObj

_setParent, exportMoML, getChildren, getElementName, getParent, getPrototypeList, isClassDefinition, isWithinClassDefinition

Methods inherited from class ptolemy.kernel.util.NamedObj

_addAttribute, _adjustOverride, _attachText, _cloneFixAttributeFields, _containedDecorators, _copyChangeRequestList, _debug, _debug, _debug, _debug, _debug, _executeChangeRequests, _getIndentPrefix, _isMoMLSuppressed, _markContentsDerived, _notifyHierarchyListenersAfterChange, _notifyHierarchyListenersBeforeChange, _propagateValue, _removeAttribute, _splitName, _stripNumericSuffix, addChangeListener, addDebugListener, addHierarchyListener, attributeDeleted, attributeList, attributeList, decorators, deepContains, depthInHierarchy, description, description, event, executeChangeRequests, exportMoML, exportMoML, exportMoML, exportMoML, exportMoMLPlain, getAttribute, getAttributes, getChangeListeners, getClassName, getDecoratorAttribute, getDecoratorAttributes, getDerivedLevel, getDerivedList, getDisplayName, getFullName, getModelErrorHandler, getName, getName, getSource, handleModelError, isDeferringChangeRequests, isOverridden, isPersistent, lazyContainedObjectsIterator, message, notifyOfNameChange, propagateValue, propagateValues, removeAttribute, removeChangeListener, removeDebugListener, removeHierarchyListener, requestChange, setClassName, setDeferringChangeRequests, setDerivedLevel, setDisplayName, setModelErrorHandler, setPersistent, setSource, sortContainedObjects, toplevel, toString, validateSettables, workspace

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface ptolemy.kernel.util.Nameable

description, getContainer, getDisplayName, getFullName, getName, getName, setName

Methods inherited from interface ptolemy.actor.Actor

createReceivers, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, newReceiver, outputPortList

Methods inherited from interface ptolemy.actor.Executable

isFireFunctional, isStrict, iterate, postfire, prefire, stop, stopFire, terminate

Methods inherited from interface ptolemy.actor.Initializable

addInitializable, preinitialize, removeInitializable

Methods inherited from interface ptolemy.kernel.util.Derivable

getDerivedLevel, getDerivedList, propagateValue

Field Detail

preemptive

public Parameter preemptive

Parameter to configure whether a preemptive or non-preemptive scheduling strategy should be used. The default value is the boolean value true.

LOWEST_PRIORITY

public static int LOWEST_PRIORITY

Lowest task priority.

_currentlyExecuting

protected java.util.Stack<NamedObj> _currentlyExecuting

Stack of currently executing actors.

Constructor Detail

FixedPriorityScheduler

public FixedPriorityScheduler(CompositeEntity container,
                              java.lang.String name)
                       throws IllegalActionException,
                              NameDuplicationException

Create a new actor in the specified container with the specified name. The name must be unique within the container or an exception is thrown. The container argument must not be null, or a NullPointerException will be thrown.

Parameters:

container - The container.

name - The name of this actor within the container.

Throws:

IllegalActionException - If this actor cannot be contained by the proposed container (see the setContainer() method).

NameDuplicationException - If the name coincides with an entity already in the container.

Method Detail

attributeChanged

public void attributeChanged(Attribute attribute)
                      throws IllegalActionException

If the attribute is preemptive then change the scheduling algorithm to be preemptive or non-preemptive.

Overrides:

attributeChanged in class NamedObj

Parameters:

attribute - The attribute that changed.

Throws:

IllegalActionException - If the change is not acceptable to this container (not thrown in this base class).

clone

public java.lang.Object clone(Workspace workspace)
                       throws java.lang.CloneNotSupportedException

Clone the actor into the specified workspace.

Overrides:

clone in class AtomicExecutionAspect

Parameters:

workspace - The workspace for the new object.

Returns:

A new actor.

Throws:

java.lang.CloneNotSupportedException - If a derived class contains an attribute that cannot be cloned.

See Also:

NamedObj.exportMoML(Writer, int, String), NamedObj.setDeferringChangeRequests(boolean)

createDecoratorAttributes

public DecoratorAttributes createDecoratorAttributes(NamedObj target)

Return the decorated attributes for the target NamedObj. If the specified target is not an Actor, return null.

Specified by:

createDecoratorAttributes in interface Decorator

Overrides:

createDecoratorAttributes in class AtomicExecutionAspect

Parameters:

target - The NamedObj that will be decorated.

Returns:

The decorated attributes for the target NamedObj, or null if the specified target is not an Actor.

initialize

public void initialize()
                throws IllegalActionException

Initialize local variables.

Specified by:

initialize in interface Initializable

Overrides:

initialize in class AtomicExecutionAspect

Throws:

IllegalActionException - Thrown in super class.

schedule

public Time schedule(Time environmentTime)
              throws IllegalActionException

Perform rescheduling actions when no new actor requests to be scheduled.

Specified by:

schedule in interface ActorExecutionAspect

Overrides:

schedule in class AtomicExecutionAspect

Parameters:

environmentTime - The outside time.

Returns:

Relative time when this aspect has to be executed again to perform rescheduling actions.

Throws:

IllegalActionException - Thrown in subclasses.

schedule

public Time schedule(NamedObj actor,
                     Time currentPlatformTime,
                     Time deadline,
                     Time executionTime)
              throws IllegalActionException

Schedule a new actor for execution and return the next time this aspect has to perform a reschedule.

Specified by:

schedule in interface ActorExecutionAspect

Overrides:

schedule in class AtomicExecutionAspect

Parameters:

actor - The actor to be scheduled.

currentPlatformTime - The current platform time.

deadline - The event deadline - not used here.

executionTime - The execution time of the actor.

Returns:

Relative time when this aspect has to be executed again.

Throws:

IllegalActionException - Thrown if actor parameters such as execution time or priority cannot be read.

_getPriority

protected double _getPriority(NamedObj actor)
                       throws IllegalActionException

Get the priority of the actor.

Parameters:

actor - The actor.

Returns:

The priority of the actor or, if the actor has no priority assigned, the lowest priority.

Throws:

IllegalActionException - Thrown if parameter cannot be read.