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ns3::CalendarScheduler Class Reference

a calendar queue event scheduler More...

#include <calendar-scheduler.h>

+ Inheritance diagram for ns3::CalendarScheduler:

Public Member Functions

virtual void Insert (const Event &ev)
 
virtual bool IsEmpty (void) const
 
virtual Event PeekNext (void) const
 
virtual void Remove (const Event &ev)
 
virtual Event RemoveNext (void)
 
- Public Member Functions inherited from ns3::Object
void AggregateObject (Ptr< Object > other)
 
void Dispose (void)
 
AggregateIterator GetAggregateIterator (void) const
 
virtual TypeId GetInstanceTypeId (void) const
 
template<typename T >
Ptr< T > GetObject (void) const
 
template<typename T >
Ptr< T > GetObject (TypeId tid) const
 
void Initialize (void)
 
- Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
 SimpleRefCount (const SimpleRefCount &o)
 
uint32_t GetReferenceCount (void) const
 
SimpleRefCountoperator= (const SimpleRefCount &o)
 
void Ref (void) const
 
void Unref (void) const
 
- Public Member Functions inherited from ns3::ObjectBase
void GetAttribute (std::string name, AttributeValue &value) const
 
bool GetAttributeFailSafe (std::string name, AttributeValue &attribute) const
 
void SetAttribute (std::string name, const AttributeValue &value)
 
bool SetAttributeFailSafe (std::string name, const AttributeValue &value)
 
bool TraceConnect (std::string name, std::string context, const CallbackBase &cb)
 
bool TraceConnectWithoutContext (std::string name, const CallbackBase &cb)
 
bool TraceDisconnect (std::string name, std::string context, const CallbackBase &cb)
 
bool TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb)
 

Static Public Member Functions

static TypeId GetTypeId (void)
 
- Static Public Member Functions inherited from ns3::Scheduler
static TypeId GetTypeId (void)
 
- Static Public Member Functions inherited from ns3::Object
static TypeId GetTypeId (void)
 
- Static Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
static void Cleanup (void)
 
- Static Public Member Functions inherited from ns3::ObjectBase
static TypeId GetTypeId (void)
 

Private Types

typedef std::list
< Scheduler::Event
Bucket
 

Private Member Functions

uint32_t CalculateNewWidth (void)
 
void DoInsert (const Event &ev)
 
Scheduler::Event DoRemoveNext (void)
 
void DoResize (uint32_t newSize, uint32_t newWidth)
 
uint32_t Hash (uint64_t key) const
 
void Init (uint32_t nBuckets, uint64_t width, uint64_t startPrio)
 
void PrintInfo (void)
 
void Resize (uint32_t newSize)
 
void ResizeDown (void)
 
void ResizeUp (void)
 

Private Attributes

Bucket * m_buckets
 
uint64_t m_bucketTop
 
uint32_t m_lastBucket
 
uint64_t m_lastPrio
 
uint32_t m_nBuckets
 
uint32_t m_qSize
 
uint64_t m_width
 

Additional Inherited Members

- Protected Member Functions inherited from ns3::Object
 Object (const Object &o)
 
virtual void DoDispose (void)
 
virtual void DoInitialize (void)
 
virtual void NotifyNewAggregate (void)
 
- Protected Member Functions inherited from ns3::ObjectBase
void ConstructSelf (const AttributeConstructionList &attributes)
 
virtual void NotifyConstructionCompleted (void)
 

Detailed Description

a calendar queue event scheduler

This event scheduler is a direct implementation of the algorithm known as a calendar queue. first published in 1988 in "Calendar Queues: A Fast O(1) Priority Queue Implementation for the Simulation Event Set Problem" by Randy Brown. There are many refinements published later but this class implements the original algorithm (to the best of my knowledge).

Note: This queue is much slower than I expected (much slower than the std::map queue) and this seems to be because the original resizing policy is horribly bad. This is most likely the reason why there have been so many variations published which all slightly tweak the resizing heuristics to obtain a better distribution of events across buckets.

Doxygen introspection did not find any typical Config paths.
No Attributes are defined for this type.
No TraceSources are defined for this type.

Definition at line 47 of file calendar-scheduler.h.

Member Function Documentation

void ns3::CalendarScheduler::Insert ( const Event ev)
virtual
Parameters
evevent to store in the event list

Implements ns3::Scheduler.

Definition at line 114 of file calendar-scheduler.cc.

References NS_LOG_FUNCTION.

bool ns3::CalendarScheduler::IsEmpty ( void  ) const
virtual
Returns
true if the event list is empty and false otherwise.

Implements ns3::Scheduler.

Definition at line 122 of file calendar-scheduler.cc.

References NS_LOG_FUNCTION.

Referenced by PeekNext(), Remove(), and RemoveNext().

Scheduler::Event ns3::CalendarScheduler::PeekNext ( void  ) const
virtual
Returns
a pointer to the next earliest event. The caller takes ownership of the returned pointer.

This method cannot be invoked if the list is empty.

Implements ns3::Scheduler.

Definition at line 128 of file calendar-scheduler.cc.

References IsEmpty(), NS_ASSERT, and NS_LOG_FUNCTION.

void ns3::CalendarScheduler::Remove ( const Event ev)
virtual
Parameters
evthe event to remove

This methods cannot be invoked if the list is empty.

Implements ns3::Scheduler.

Definition at line 221 of file calendar-scheduler.cc.

References IsEmpty(), NS_ASSERT, and NS_LOG_FUNCTION.

Scheduler::Event ns3::CalendarScheduler::RemoveNext ( void  )
virtual

This method cannot be invoked if the list is empty. Remove the next earliest event from the event list.

Implements ns3::Scheduler.

Definition at line 206 of file calendar-scheduler.cc.

References IsEmpty(), NS_ASSERT, NS_LOG_FUNCTION, and NS_LOG_LOGIC.


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