Scheduler Class Reference

#include <Scheduler.h>

Inherited by PriorityScheduler, and PseudoScheduler.

List of all members.

---

Detailed Description

A scheduler in charge of running boxes in a catalog.

An AuroraNode has an associated scheduler responsible for managing box invocation.

AuroraNode::start() calls Scheduler::start(), which should create one or more threads to run boxes. AuroraNode::shutdown() calls Scheduler::shutdown(), which should signal for those threads to stop and wait for their termination (i.e., join them).

AuroraNode may call scheduleExclusiveTask() to request that some code be run exclusively of all boxes. This is useful when AuroraNode must make some change to the topology of the network (currently limited to adding/removing subscriptions to streams).

Public Types
typedef Registry< Scheduler >	Registry
Public Member Functions
virtual	~Scheduler ()
AuroraNode &	node ()
	Returns the node associated with this scheduler.
virtual void	start ()=0
	Called when a node is started.
virtual void	shutdown ()=0
	Called when a node is stopped.
virtual void	scheduleExclusiveTask (ptr< SchedulerTask >)=0
	Schedules a task to be run as soon as possible, at some point when no boxes are running.
virtual void	topologyChanged ()
	Invoked when the network topology changes, i.e., one or more boxes or streams were added or removed.
bool	hasDynamicSupport ()
	Returns true iff the scheduler supports dynamic networks (née MMH2).
virtual void	drain ()
	Drains the network: waits until there are no more tuples at all in the network and then shuts the network.
bool	hasDrain ()
	Returns true iff the scheduler support draining.
virtual void	invalidateBoxes (vector< string > boxNames)
virtual void	updateListeners (vector< string > boxNames, bool add)
virtual void	chokeSubNetwork (vector< string > boxNames)
virtual void	suspendSubNetwork (vector< string > boxNames)
virtual void	resumeSubNetwork (vector< string > boxNames)
virtual void	drainSubNetwork (vector< string > boxNames)
virtual void	removeFromSchedule (QBox *box)
virtual string	to_string ()
virtual void	init_sched_stats (int windowSize, int historySize)
Static Public Member Functions
unsigned long	ticks ()
double	secondsPerTick ()
unsigned long	ticksPerSecond ()
Public Attributes
SchedulerStats	_sched_stats
Protected Member Functions
void	setBoxData (QBox &box, ptr< BoxData > data)
BoxData *	getBoxData (const QBox &box) const
	Scheduler (bool dynamic_support=false, bool drain_support=false)
	Constructor.
Protected Attributes
unsigned int	_init_time

---

Member Typedef Documentation

typedef Registry<Scheduler> Scheduler::Registry

---

Constructor & Destructor Documentation

Scheduler::~Scheduler (   )  [virtual]

Scheduler::Scheduler (  bool  dynamic_support = false, bool  drain_support = false )  [protected]

Constructor. Parameters: dynamic_support  indicates whether the scheduler implementation supports dynamic networks. drain_support  indicates whether the scheduler implementation supports draining.

---

Member Function Documentation

void Scheduler::chokeSubNetwork (  vector< string >  boxNames  )  [virtual]

virtual void Scheduler::drain (   )  [virtual]

Drains the network: waits until there are no more tuples at all in the network and then shuts the network. Blocks until this is complete, at which point the only valid operation is shutdown(). May be invoked only if the scheduler supports draining. Reimplemented in PriorityScheduler, and PseudoScheduler.

void Scheduler::drainSubNetwork (  vector< string >  boxNames  )  [virtual]

Scheduler::BoxData * Scheduler::getBoxData (  const QBox &  box  )  const [protected]

bool Scheduler::hasDrain (   )

Returns true iff the scheduler support draining.

bool Scheduler::hasDynamicSupport (   )

Returns true iff the scheduler supports dynamic networks (née MMH2).

void Scheduler::init_sched_stats (  int  windowSize, int  historySize )  [virtual]

void Scheduler::invalidateBoxes (  vector< string >  boxNames  )  [virtual]

AuroraNode& Scheduler::node (   )

Returns the node associated with this scheduler. Scheduler code may invoke this to gain access to the node's catalog.

virtual void Scheduler::removeFromSchedule (  QBox *  box  )  [virtual]

Reimplemented in PseudoScheduler.

void Scheduler::resumeSubNetwork (  vector< string >  boxNames  )  [virtual]

virtual void Scheduler::scheduleExclusiveTask (  ptr< SchedulerTask >   )  [pure virtual]

Schedules a task to be run as soon as possible, at some point when no boxes are running. For example, the scheduler may maintain a thread-safe vector of ptr<SchedulerTask>s. Whenever this vector becomes non-empty, it can signal box-running threads to pause; wait for all pending run() calls to complete; and then run the tasks in one of the box-running threads. Implemented in PriorityScheduler, and PseudoScheduler.

double Scheduler::secondsPerTick (   )  [static]

void Scheduler::setBoxData (  QBox &  box, ptr< BoxData >  data )  [protected]

virtual void Scheduler::shutdown (   )  [pure virtual]

Called when a node is stopped. The implementation of this method must stop any threads that are running boxes and wait for their termination (i.e., join them). Implemented in PriorityScheduler, and PseudoScheduler.

virtual void Scheduler::start (   )  [pure virtual]

Called when a node is started. The implementation of this method should create one or more threads to run boxes. Implemented in PriorityScheduler, and PseudoScheduler.

void Scheduler::suspendSubNetwork (  vector< string >  boxNames  )  [virtual]

unsigned long Scheduler::ticks (   )  [static]

unsigned long Scheduler::ticksPerSecond (   )  [static]

string Scheduler::to_string (   )  [virtual]

virtual void Scheduler::topologyChanged (   )  [virtual]

Invoked when the network topology changes, i.e., one or more boxes or streams were added or removed. This method may only be invoked from within an exclusive task (since the network topology may only change within an exclusive task), and only if the scheduler supports dynamic networks. Reimplemented in PriorityScheduler, and PseudoScheduler.

void Scheduler::updateListeners (  vector< string >  boxNames, bool  add )  [virtual]

---

Member Data Documentation

unsigned int Scheduler::_init_time [protected]

SchedulerStats Scheduler::_sched_stats

---

The documentation for this class was generated from the following files:

• Scheduler.h
• QBox.h
• Scheduler.cc

---