31 #include "ns3/packet.h"
32 #include "ns3/queue-disc.h"
33 #include "ns3/nstime.h"
34 #include "ns3/simulator.h"
35 #include "ns3/string.h"
36 #include "ns3/traced-value.h"
37 #include "ns3/trace-source-accessor.h"
50 #define DEFAULT_CODEL_LIMIT 1000
51 #define REC_INV_SQRT_BITS (8 * sizeof(uint16_t))
52 #define REC_INV_SQRT_SHIFT (32 - REC_INV_SQRT_BITS)
139 friend class::CoDelQueueDiscNewtonStepTest;
140 friend class::CoDelQueueDiscControlLawTest;
virtual void InitializeParams(void)
Initialize parameters (if any) before the first packet is enqueued.
virtual Ptr< const QueueDiscItem > DoPeek(void) const
This function returns a copy of the next packet the queue disc will extract.
Queue::QueueMode m_mode
The operating mode (Bytes or packets)
Simulation virtual time values and global simulation resolution.
virtual bool DoEnqueue(Ptr< QueueDiscItem > item)
Add a packet to the queue.
uint32_t m_maxBytes
Max # of bytes accepted by the queue.
Smart pointer class similar to boost::intrusive_ptr.
TracedValue< uint32_t > m_dropCount
Number of dropped packets according CoDel algorithm.
uint32_t m_maxPackets
Max # of packets accepted by the queue.
uint32_t GetDropOverLimit(void)
Get the number of packets dropped when packets arrive at a full queue and cannot be enqueued...
TracedValue< Time > m_sojourn
Time in queue.
uint32_t GetDropNext(void)
Get the time for next packet drop while in the dropping state.
TracedValue< uint32_t > m_count
Number of packets dropped since entering drop state.
virtual bool CheckConfig(void)
Check whether the current configuration is correct.
bool OkToDrop(Ptr< Packet > p, uint32_t now)
Determine whether a packet is OK to be dropped.
Time GetInterval(void)
Get the interval.
bool CoDelTimeAfterEq(uint32_t a, uint32_t b)
Check if CoDel time a is successive or equal to b.
QueueDisc is an abstract base class providing the interface and implementing the operations common to...
uint32_t ControlLaw(uint32_t t)
Determine the time for next drop CoDel control law is t + m_interval/sqrt(m_count).
bool CoDelTimeAfter(uint32_t a, uint32_t b)
Check if CoDel time a is successive to b.
TracedValue< bool > m_dropping
True if in dropping state.
uint32_t m_dropOverLimit
The number of packets dropped due to full queue.
Queue::QueueMode GetMode(void)
Get the encapsulation mode of this device.
uint32_t m_states
Total number of times we are in state 1, state 2, or state 3.
uint32_t m_firstAboveTime
Time to declare sojourn time above target.
uint32_t m_state2
Number of times we perform next drop while in dropping state.
bool CoDelTimeBefore(uint32_t a, uint32_t b)
Check if CoDel time a is preceding b.
Time m_target
5 ms target queue delay
CoDelQueueDisc()
CoDelQueueDisc Constructor.
virtual ~CoDelQueueDisc()
uint32_t GetQueueSize(void)
Get the current value of the queue in bytes or packets.
uint32_t GetDropCount(void)
Get the number of packets dropped according to CoDel algorithm.
TracedValue< uint32_t > m_lastCount
Last number of packets dropped since entering drop state.
Time m_interval
100 ms sliding minimum time window width
virtual Ptr< QueueDiscItem > DoDequeue(void)
Remove a packet from queue based on the current state If we are in dropping state, check if we could leave the dropping state or if we should perform next drop If we are not currently in dropping state, check if we need to enter the state and drop the first packet.
uint16_t m_recInvSqrt
Reciprocal inverse square root.
Time GetTarget(void)
Get the target queue delay.
void NewtonStep(void)
Calculate the reciprocal square root of m_count by using Newton's method http://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Iterative_methods_for_reciprocal_square_roots m_recInvSqrt (new) = (m_recInvSqrt (old) / 2) * (3 - m_count * m_recInvSqrt^2)
A CoDel packet queue disc.
static const int CODEL_SHIFT
Number of bits discarded from the time representation.
QueueMode
Enumeration of the modes supported in the class.
uint32_t m_state3
Number of times we enter drop state and drop the fist packet.
uint32_t Time2CoDel(Time t)
returned unsigned 32-bit integer representation of the input Time object units are microseconds ...
static TypeId GetTypeId(void)
Get the type ID.
bool CoDelTimeBeforeEq(uint32_t a, uint32_t b)
Check if CoDel time a is preceding or equal to b.
uint32_t m_minBytes
Minimum bytes in queue to allow a packet drop.
void SetMode(Queue::QueueMode mode)
Set the operating mode of this device.
uint32_t m_state1
Number of times packet sojourn goes above target for interval.
a unique identifier for an interface.
TracedValue< uint32_t > m_dropNext
Time to drop next packet.