31 #include "ns3/queue-disc.h"
32 #include "ns3/nstime.h"
33 #include "ns3/simulator.h"
34 #include "ns3/string.h"
35 #include "ns3/traced-value.h"
36 #include "ns3/trace-source-accessor.h"
49 #define DEFAULT_CODEL_LIMIT 1000
50 #define REC_INV_SQRT_BITS (8 * sizeof(uint16_t))
51 #define REC_INV_SQRT_SHIFT (32 - REC_INV_SQRT_BITS)
174 friend class::CoDelQueueDiscNewtonStepTest;
175 friend class::CoDelQueueDiscControlLawTest;
virtual void InitializeParams(void)
Initialize parameters (if any) before the first packet is enqueued.
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.
static constexpr const char * TARGET_EXCEEDED_DROP
Sojourn time above target.
uint32_t m_maxPackets
Max # of packets accepted by the queue.
uint32_t GetDropNext(void)
Get the time for next packet drop while in the dropping state.
QueueDiscMode GetMode(void) const
Get the operating mode of this queue disc.
TracedValue< uint32_t > m_count
Number of packets dropped since entering drop state.
static constexpr const char * OVERLIMIT_DROP
Overlimit dropped packet.
virtual bool CheckConfig(void)
Check whether the current configuration is correct.
Time GetInterval(void)
Get the interval.
Test 3: NewtonStep unit test - test against explicit port of Linux implementation.
bool CoDelTimeAfterEq(uint32_t a, uint32_t b)
Check if CoDel time a is successive or equal to b.
QueueDiscMode m_mode
The operating mode (Bytes or packets)
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.
virtual Ptr< const QueueDiscItem > DoPeek(void)
This function returns a copy of the next packet the queue disc will extract.
TracedValue< bool > m_dropping
True if in dropping state.
bool OkToDrop(Ptr< QueueDiscItem > item, uint32_t now)
Determine whether a packet is OK to be dropped.
void SetMaxPackets(uint32_t maxPackets)
Set the maximum amount of packets that can be stored in this queue.
void SetMaxBytes(uint32_t maxBytes)
Set the maximum amount of bytes that can be stored in this queue.
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.
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.
Every class exported by the ns3 library is enclosed in the ns3 namespace.
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.
uint32_t GetMaxBytes(void) const
uint32_t m_state3
Number of times we enter drop state and drop the fist packet.
uint32_t Time2CoDel(Time t)
Return the unsigned 32-bit integer representation of the input Time object.
uint32_t GetMaxPackets(void) const
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.
void SetMode(QueueDiscMode mode)
Set the operating mode of this queue disc.
uint32_t m_minBytes
Minimum bytes in queue to allow a packet drop.
Use number of bytes for maximum queue disc size.
QueueDiscMode
Enumeration of the modes supported in the class.
Use number of packets for maximum queue disc size.
uint32_t m_state1
Number of times packet sojourn goes above target for interval.
Test 4: ControlLaw unit test - test against explicit port of Linux implementation.
a unique identifier for an interface.
TracedValue< uint32_t > m_dropNext
Time to drop next packet.