A CoDel packet queue disc. More...
#include "codel-queue-disc.h"
Public Member Functions | |
CoDelQueueDisc () | |
CoDelQueueDisc Constructor. More... | |
~CoDelQueueDisc () override | |
uint32_t | GetDropNext () |
Get the time for next packet drop while in the dropping state. More... | |
Time | GetInterval () |
Get the interval. More... | |
Time | GetTarget () |
Get the target queue delay. More... | |
Public Member Functions inherited from ns3::QueueDisc | |
QueueDisc (const QueueDisc &)=delete | |
QueueDisc (QueueDiscSizePolicy policy, QueueSizeUnit unit) | |
Constructor. More... | |
QueueDisc (QueueDiscSizePolicy policy=QueueDiscSizePolicy::SINGLE_INTERNAL_QUEUE) | |
Constructor. More... | |
~QueueDisc () override | |
void | AddInternalQueue (Ptr< InternalQueue > queue) |
Add an internal queue to the tail of the list of queues. More... | |
void | AddPacketFilter (Ptr< PacketFilter > filter) |
Add a packet filter to the tail of the list of filters used to classify packets. More... | |
void | AddQueueDiscClass (Ptr< QueueDiscClass > qdClass) |
Add a queue disc class to the tail of the list of classes. More... | |
int32_t | Classify (Ptr< QueueDiscItem > item) |
Classify a packet by calling the packet filters, one at a time, until either a filter able to classify the packet is found or all the filters have been processed. More... | |
Ptr< QueueDiscItem > | Dequeue () |
Extract from the queue disc the packet that has been dequeued by calling Peek, if any, or call the private DoDequeue method (which must be implemented by derived classes) to dequeue a packet, otherwise. More... | |
bool | Enqueue (Ptr< QueueDiscItem > item) |
Pass a packet to store to the queue discipline. More... | |
QueueSize | GetCurrentSize () const |
Get the current size of the queue disc in bytes, if operating in bytes mode, or packets, otherwise. More... | |
Ptr< InternalQueue > | GetInternalQueue (std::size_t i) const |
Get the i-th internal queue. More... | |
QueueSize | GetMaxSize () const |
Get the maximum size of the queue disc. More... | |
uint32_t | GetNBytes () const |
Get the amount of bytes stored by the queue disc. More... | |
Ptr< NetDeviceQueueInterface > | GetNetDeviceQueueInterface () const |
std::size_t | GetNInternalQueues () const |
Get the number of internal queues. More... | |
std::size_t | GetNPacketFilters () const |
Get the number of packet filters. More... | |
uint32_t | GetNPackets () const |
Get the number of packets stored by the queue disc. More... | |
std::size_t | GetNQueueDiscClasses () const |
Get the number of queue disc classes. More... | |
Ptr< PacketFilter > | GetPacketFilter (std::size_t i) const |
Get the i-th packet filter. More... | |
Ptr< QueueDiscClass > | GetQueueDiscClass (std::size_t i) const |
Get the i-th queue disc class. More... | |
virtual uint32_t | GetQuota () const |
Get the maximum number of dequeue operations following a packet enqueue. More... | |
SendCallback | GetSendCallback () const |
const Stats & | GetStats () |
Retrieve all the collected statistics. More... | |
virtual WakeMode | GetWakeMode () const |
When setting up the wake callbacks on the netdevice queues, it is necessary to determine which queue disc (the root queue disc or one of its children) should be activated when the netdevice wakes one of its transmission queues. More... | |
QueueDisc & | operator= (const QueueDisc &)=delete |
Ptr< const QueueDiscItem > | Peek () |
Get a copy of the next packet the queue discipline will extract. More... | |
void | Run () |
Modelled after the Linux function __qdisc_run (net/sched/sch_generic.c) Dequeues multiple packets, until a quota is exceeded or sending a packet to the device failed. More... | |
bool | SetMaxSize (QueueSize size) |
Set the maximum size of the queue disc. More... | |
void | SetNetDeviceQueueInterface (Ptr< NetDeviceQueueInterface > ndqi) |
virtual void | SetQuota (const uint32_t quota) |
Set the maximum number of dequeue operations following a packet enqueue. More... | |
void | SetSendCallback (SendCallback func) |
Public Member Functions inherited from ns3::Object | |
Object () | |
Constructor. More... | |
~Object () override | |
Destructor. More... | |
void | AggregateObject (Ptr< Object > other) |
Aggregate two Objects together. More... | |
void | Dispose () |
Dispose of this Object. More... | |
AggregateIterator | GetAggregateIterator () const |
Get an iterator to the Objects aggregated to this one. More... | |
TypeId | GetInstanceTypeId () const override |
Get the most derived TypeId for this Object. More... | |
template<typename T > | |
Ptr< T > | GetObject () const |
Get a pointer to the requested aggregated Object. More... | |
template<> | |
Ptr< Object > | GetObject () const |
Specialization of () for objects of type ns3::Object. More... | |
template<typename T > | |
Ptr< T > | GetObject (TypeId tid) const |
Get a pointer to the requested aggregated Object by TypeId. More... | |
template<> | |
Ptr< Object > | GetObject (TypeId tid) const |
Specialization of (TypeId tid) for objects of type ns3::Object. More... | |
void | Initialize () |
Invoke DoInitialize on all Objects aggregated to this one. More... | |
bool | IsInitialized () const |
Check if the object has been initialized. More... | |
Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter > | |
SimpleRefCount () | |
Default constructor. More... | |
SimpleRefCount (const SimpleRefCount &o[[maybe_unused]]) | |
Copy constructor. More... | |
uint32_t | GetReferenceCount () const |
Get the reference count of the object. More... | |
SimpleRefCount & | operator= (const SimpleRefCount &o[[maybe_unused]]) |
Assignment operator. More... | |
void | Ref () const |
Increment the reference count. More... | |
void | Unref () const |
Decrement the reference count. More... | |
Public Member Functions inherited from ns3::ObjectBase | |
virtual | ~ObjectBase () |
Virtual destructor. More... | |
void | GetAttribute (std::string name, AttributeValue &value) const |
Get the value of an attribute, raising fatal errors if unsuccessful. More... | |
bool | GetAttributeFailSafe (std::string name, AttributeValue &value) const |
Get the value of an attribute without raising errors. More... | |
void | SetAttribute (std::string name, const AttributeValue &value) |
Set a single attribute, raising fatal errors if unsuccessful. More... | |
bool | SetAttributeFailSafe (std::string name, const AttributeValue &value) |
Set a single attribute without raising errors. More... | |
bool | TraceConnect (std::string name, std::string context, const CallbackBase &cb) |
Connect a TraceSource to a Callback with a context. More... | |
bool | TraceConnectWithoutContext (std::string name, const CallbackBase &cb) |
Connect a TraceSource to a Callback without a context. More... | |
bool | TraceDisconnect (std::string name, std::string context, const CallbackBase &cb) |
Disconnect from a TraceSource a Callback previously connected with a context. More... | |
bool | TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb) |
Disconnect from a TraceSource a Callback previously connected without a context. More... | |
Static Public Member Functions | |
static TypeId | GetTypeId () |
Get the type ID. More... | |
Static Public Member Functions inherited from ns3::QueueDisc | |
static TypeId | GetTypeId () |
Get the type ID. More... | |
Static Public Member Functions inherited from ns3::Object | |
static TypeId | GetTypeId () |
Register this type. More... | |
Static Public Member Functions inherited from ns3::ObjectBase | |
static TypeId | GetTypeId () |
Get the type ID. More... | |
Static Public Attributes | |
static constexpr const char * | CE_THRESHOLD_EXCEEDED_MARK |
Sojourn time above CE threshold. More... | |
static constexpr const char * | OVERLIMIT_DROP = "Overlimit drop" |
Overlimit dropped packet. More... | |
static constexpr const char * | TARGET_EXCEEDED_DROP |
Sojourn time above target. More... | |
static constexpr const char * | TARGET_EXCEEDED_MARK |
Sojourn time above target. More... | |
Static Public Attributes inherited from ns3::QueueDisc | |
static constexpr const char * | CHILD_QUEUE_DISC_DROP |
Packet dropped by a child queue disc. More... | |
static constexpr const char * | CHILD_QUEUE_DISC_MARK |
Packet marked by a child queue disc. More... | |
static constexpr const char * | INTERNAL_QUEUE_DROP |
Packet dropped by an internal queue. More... | |
Private Member Functions | |
bool | CheckConfig () override |
Check whether the current configuration is correct. More... | |
bool | CoDelTimeAfter (uint32_t a, uint32_t b) |
Check if CoDel time a is successive to b. More... | |
bool | CoDelTimeAfterEq (uint32_t a, uint32_t b) |
Check if CoDel time a is successive or equal to b. More... | |
bool | CoDelTimeBefore (uint32_t a, uint32_t b) |
Check if CoDel time a is preceding b. More... | |
bool | CoDelTimeBeforeEq (uint32_t a, uint32_t b) |
Check if CoDel time a is preceding or equal to b. More... | |
Ptr< QueueDiscItem > | DoDequeue () override |
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. More... | |
bool | DoEnqueue (Ptr< QueueDiscItem > item) override |
Add a packet to the queue. More... | |
void | InitializeParams () override |
Initialize parameters (if any) before the first packet is enqueued. More... | |
bool | OkToDrop (Ptr< QueueDiscItem > item, uint32_t now) |
Determine whether a packet is OK to be dropped. More... | |
uint32_t | Time2CoDel (Time t) |
Return the unsigned 32-bit integer representation of the input Time object. More... | |
Static Private Member Functions | |
static uint32_t | ControlLaw (uint32_t t, uint32_t interval, uint32_t recInvSqrt) |
Determine the time for next drop CoDel control law is t + m_interval/sqrt(m_count). More... | |
static uint16_t | NewtonStep (uint16_t recInvSqrt, uint32_t count) |
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) More... | |
Private Attributes | |
Time | m_ceThreshold |
Threshold above which to CE mark. More... | |
TracedValue< uint32_t > | m_count |
Number of packets dropped since entering drop state. More... | |
TracedValue< uint32_t > | m_dropNext |
Time to drop next packet. More... | |
TracedValue< bool > | m_dropping |
True if in dropping state. More... | |
uint32_t | m_firstAboveTime |
Time to declare sojourn time above target. More... | |
Time | m_interval |
100 ms sliding minimum time window width More... | |
TracedValue< uint32_t > | m_lastCount |
Last number of packets dropped since entering drop state. More... | |
uint32_t | m_minBytes |
Minimum bytes in queue to allow a packet drop. More... | |
uint16_t | m_recInvSqrt |
Reciprocal inverse square root. More... | |
Time | m_target |
5 ms target queue delay More... | |
bool | m_useEcn |
True if ECN is used (packets are marked instead of being dropped) More... | |
bool | m_useL4s |
True if L4S is used (ECT1 packets are marked at CE threshold) More... | |
Friends | |
class | ::CoDelQueueDiscControlLawTest |
class | ::CoDelQueueDiscNewtonStepTest |
Additional Inherited Members | |
Public Types inherited from ns3::QueueDisc | |
typedef Queue< QueueDiscItem > | InternalQueue |
Internal queues store QueueDiscItem objects. More... | |
typedef std::function< void(Ptr< QueueDiscItem >)> | SendCallback |
Callback invoked to send a packet to the receiving object when Run is called. More... | |
enum | WakeMode { WAKE_ROOT = 0x00 , WAKE_CHILD = 0x01 } |
Used to determine whether the queue disc itself or its children must be activated when a netdevice wakes a transmission queue. More... | |
Protected Member Functions inherited from ns3::QueueDisc | |
void | DoDispose () override |
Dispose of the object. More... | |
void | DoInitialize () override |
Check whether the configuration is correct and initialize parameters. More... | |
void | DropAfterDequeue (Ptr< const QueueDiscItem > item, const char *reason) |
Perform the actions required when the queue disc is notified of a packet dropped after dequeue. More... | |
void | DropBeforeEnqueue (Ptr< const QueueDiscItem > item, const char *reason) |
Perform the actions required when the queue disc is notified of a packet dropped before enqueue. More... | |
bool | Mark (Ptr< QueueDiscItem > item, const char *reason) |
Marks the given packet and, if successful, updates the counters associated with the given reason. More... | |
Protected Member Functions inherited from ns3::Object | |
Object (const Object &o) | |
Copy an Object. More... | |
virtual void | NotifyNewAggregate () |
Notify all Objects aggregated to this one of a new Object being aggregated. More... | |
Protected Member Functions inherited from ns3::ObjectBase | |
void | ConstructSelf (const AttributeConstructionList &attributes) |
Complete construction of ObjectBase; invoked by derived classes. More... | |
virtual void | NotifyConstructionCompleted () |
Notifier called once the ObjectBase is fully constructed. More... | |
Related Functions inherited from ns3::ObjectBase | |
static TypeId | GetObjectIid () |
Ensure the TypeId for ObjectBase gets fully configured to anchor the inheritance tree properly. More... | |
A CoDel packet queue disc.
Definition at line 63 of file codel-queue-disc.h.
ns3::CoDelQueueDisc::CoDelQueueDisc | ( | ) |
CoDelQueueDisc Constructor.
Creates a CoDel queue
Definition at line 137 of file codel-queue-disc.cc.
References NS_LOG_FUNCTION.
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override |
Definition at line 149 of file codel-queue-disc.cc.
References NS_LOG_FUNCTION.
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overrideprivatevirtual |
Check whether the current configuration is correct.
Default objects (such as internal queues) might be created by this method to ensure the configuration is correct. This method is automatically called at simulation initialization time, and it is called before the InitializeParams () method. It is appropriate to promote parameter initialization to this method if it aids in checking for correct configuration.
Implements ns3::QueueDisc.
Definition at line 470 of file codel-queue-disc.cc.
References ns3::QueueDisc::AddInternalQueue(), ns3::CreateObjectWithAttributes(), ns3::QueueDisc::GetMaxSize(), ns3::QueueDisc::GetNInternalQueues(), ns3::QueueDisc::GetNPacketFilters(), ns3::QueueDisc::GetNQueueDiscClasses(), NS_LOG_ERROR, and NS_LOG_FUNCTION.
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private |
Check if CoDel time a is successive to b.
a | left operand |
b | right operand |
Definition at line 440 of file codel-queue-disc.cc.
Referenced by DoDequeue(), and OkToDrop().
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private |
Check if CoDel time a is successive or equal to b.
a | left operand |
b | right operand |
Definition at line 446 of file codel-queue-disc.cc.
Referenced by DoDequeue().
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private |
Check if CoDel time a is preceding b.
a | left operand |
b | right operand |
Definition at line 452 of file codel-queue-disc.cc.
Referenced by DoDequeue(), and OkToDrop().
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private |
Check if CoDel time a is preceding or equal to b.
a | left operand |
b | right operand |
Definition at line 458 of file codel-queue-disc.cc.
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staticprivate |
Determine the time for next drop CoDel control law is t + m_interval/sqrt(m_count).
Here, we use m_recInvSqrt calculated by Newton's method in NewtonStep() to avoid both sqrt() and divide operations
t | Current next drop time (in units of CoDel time) |
interval | interval (in units of CoDel time) |
recInvSqrt | reciprocal value of sqrt (count) |
Definition at line 168 of file codel-queue-disc.cc.
References NS_LOG_FUNCTION_NOARGS, REC_INV_SQRT_SHIFT, and ns3::ReciprocalDivide().
Referenced by DoDequeue().
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overrideprivatevirtual |
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.
Implements ns3::QueueDisc.
Definition at line 242 of file codel-queue-disc.cc.
References CE_THRESHOLD_EXCEEDED_MARK, ns3::CoDelGetTime(), CoDelTimeAfter(), CoDelTimeAfterEq(), CoDelTimeBefore(), ControlLaw(), two-ray-to-three-gpp-ch-calibration::delta, ns3::QueueDisc::DropAfterDequeue(), ns3::QueueDisc::GetInternalQueue(), ns3::QueueDisc::GetNBytes(), ns3::QueueDisc::GetNPackets(), ns3::Time::GetSeconds(), ns3::QueueItem::IP_DSFIELD, m_ceThreshold, m_count, m_dropNext, m_dropping, m_interval, m_lastCount, m_recInvSqrt, m_useEcn, m_useL4s, ns3::QueueDisc::Mark(), NewtonStep(), ns3::Simulator::Now(), NS_LOG_DEBUG, NS_LOG_FUNCTION, NS_LOG_LOGIC, OkToDrop(), REC_INV_SQRT_SHIFT, TARGET_EXCEEDED_DROP, TARGET_EXCEEDED_MARK, and Time2CoDel().
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overrideprivatevirtual |
Add a packet to the queue.
item | The item to be added |
Implements ns3::QueueDisc.
Definition at line 175 of file codel-queue-disc.cc.
References ns3::QueueDisc::DropBeforeEnqueue(), ns3::QueueDisc::GetCurrentSize(), ns3::QueueDisc::GetInternalQueue(), ns3::QueueDisc::GetMaxSize(), ns3::QueueDisc::GetNBytes(), ns3::QueueDisc::GetNPackets(), NS_LOG_FUNCTION, NS_LOG_LOGIC, and OVERLIMIT_DROP.
uint32_t ns3::CoDelQueueDisc::GetDropNext | ( | ) |
Get the time for next packet drop while in the dropping state.
Definition at line 434 of file codel-queue-disc.cc.
References m_dropNext.
Time ns3::CoDelQueueDisc::GetInterval | ( | ) |
Get the interval.
Definition at line 428 of file codel-queue-disc.cc.
References m_interval.
Time ns3::CoDelQueueDisc::GetTarget | ( | ) |
Get the target queue delay.
Definition at line 422 of file codel-queue-disc.cc.
References m_target.
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static |
Get the type ID.
Get the type ID.
Definition at line 74 of file codel-queue-disc.cc.
References ns3::BYTES, DEFAULT_CODEL_LIMIT, ns3::QueueDisc::GetMaxSize(), m_ceThreshold, m_count, m_dropNext, m_dropping, m_interval, m_lastCount, m_minBytes, m_target, m_useEcn, m_useL4s, ns3::MakeBooleanAccessor(), ns3::MakeBooleanChecker(), ns3::MakeTimeAccessor(), ns3::MakeTimeChecker(), ns3::MakeTraceSourceAccessor(), ns3::MakeUintegerAccessor(), ns3::Time::Max(), ns3::QueueDisc::SetMaxSize(), and ns3::TypeId::SetParent().
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overrideprivatevirtual |
Initialize parameters (if any) before the first packet is enqueued.
This method is automatically called at simulation initialization time, after the CheckConfig() method has been called.
Implements ns3::QueueDisc.
Definition at line 503 of file codel-queue-disc.cc.
References NS_LOG_FUNCTION.
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staticprivate |
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)
recInvSqrt | reciprocal value of sqrt (count) |
count | count value |
Definition at line 155 of file codel-queue-disc.cc.
References NS_LOG_FUNCTION_NOARGS, and REC_INV_SQRT_SHIFT.
Referenced by DoDequeue().
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private |
Determine whether a packet is OK to be dropped.
The packet may not be actually dropped (depending on the drop state)
item | The packet that is considered |
now | The current time represented as 32-bit unsigned integer (us) |
Definition at line 198 of file codel-queue-disc.cc.
References CoDelTimeAfter(), CoDelTimeBefore(), two-ray-to-three-gpp-ch-calibration::delta, ns3::QueueDisc::GetInternalQueue(), ns3::QueueDisc::GetNBytes(), m_firstAboveTime, m_interval, m_minBytes, m_target, ns3::Time::MS, ns3::Simulator::Now(), NS_LOG_FUNCTION, NS_LOG_INFO, NS_LOG_LOGIC, and Time2CoDel().
Referenced by DoDequeue().
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private |
Return the unsigned 32-bit integer representation of the input Time object.
Units are microseconds
Definition at line 464 of file codel-queue-disc.cc.
References ns3::CODEL_SHIFT, and ns3::Time::GetNanoSeconds().
Referenced by DoDequeue(), and OkToDrop().
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friend |
Definition at line 115 of file codel-queue-disc.h.
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friend |
Definition at line 114 of file codel-queue-disc.h.
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staticconstexpr |
Sojourn time above CE threshold.
Definition at line 110 of file codel-queue-disc.h.
Referenced by DoDequeue().
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private |
Threshold above which to CE mark.
Definition at line 215 of file codel-queue-disc.h.
Referenced by DoDequeue(), and GetTypeId().
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private |
Number of packets dropped since entering drop state.
Definition at line 216 of file codel-queue-disc.h.
Referenced by DoDequeue(), and GetTypeId().
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private |
Time to drop next packet.
Definition at line 221 of file codel-queue-disc.h.
Referenced by DoDequeue(), GetDropNext(), and GetTypeId().
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private |
True if in dropping state.
Definition at line 218 of file codel-queue-disc.h.
Referenced by DoDequeue(), and GetTypeId().
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private |
Time to declare sojourn time above target.
Definition at line 220 of file codel-queue-disc.h.
Referenced by OkToDrop().
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private |
100 ms sliding minimum time window width
Definition at line 213 of file codel-queue-disc.h.
Referenced by DoDequeue(), GetInterval(), GetTypeId(), and OkToDrop().
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private |
Last number of packets dropped since entering drop state.
Definition at line 217 of file codel-queue-disc.h.
Referenced by DoDequeue(), and GetTypeId().
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private |
Minimum bytes in queue to allow a packet drop.
Definition at line 212 of file codel-queue-disc.h.
Referenced by GetTypeId(), and OkToDrop().
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private |
Reciprocal inverse square root.
Definition at line 219 of file codel-queue-disc.h.
Referenced by DoDequeue().
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private |
5 ms target queue delay
Definition at line 214 of file codel-queue-disc.h.
Referenced by GetTarget(), GetTypeId(), and OkToDrop().
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private |
True if ECN is used (packets are marked instead of being dropped)
Definition at line 210 of file codel-queue-disc.h.
Referenced by DoDequeue(), and GetTypeId().
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private |
True if L4S is used (ECT1 packets are marked at CE threshold)
Definition at line 211 of file codel-queue-disc.h.
Referenced by DoDequeue(), and GetTypeId().
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staticconstexpr |
Overlimit dropped packet.
Definition at line 106 of file codel-queue-disc.h.
Referenced by DoEnqueue().
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staticconstexpr |
Sojourn time above target.
Definition at line 104 of file codel-queue-disc.h.
Referenced by DoDequeue().
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staticconstexpr |
Sojourn time above target.
Definition at line 108 of file codel-queue-disc.h.
Referenced by DoDequeue().