Files
aya/third-party/RakNet/src/RakNet/CCRakNetUDT.cpp
2025-12-17 16:47:48 +00:00

799 lines
26 KiB
C++

#include "CCRakNetUDT.hpp"
#if USE_SLIDING_WINDOW_CONGESTION_CONTROL!=1
#include "Rand.hpp"
#include "MTUSize.hpp"
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
//#include <memory.h>
#include "RakAssert.hpp"
#include "RakAlloca.hpp"
using namespace RakNet;
static const double UNSET_TIME_US=-1;
static const double CWND_MIN_THRESHOLD=2.0;
static const double UNDEFINED_TRANSFER_RATE=0.0;
/// Interval at which to update aspects of the system
/// 1. send acks
/// 2. update time interval between outgoing packets
/// 3, Yodate retransmit timeout
#if CC_TIME_TYPE_BYTES==4
static const CCTimeType SYN=10;
#else
static const CCTimeType SYN=10000;
#endif
#if CC_TIME_TYPE_BYTES==4
#define MAX_RTT 1000
#define RTT_TOLERANCE 30
#else
#define MAX_RTT 1000000
#define RTT_TOLERANCE 30000
#endif
double RTTVarMultiple=4.0;
// ****************************************************** PUBLIC METHODS ******************************************************
CCRakNetUDT::CCRakNetUDT()
{
}
// ----------------------------------------------------------------------------------------------------------------------------
CCRakNetUDT::~CCRakNetUDT()
{
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::Init(CCTimeType curTime, uint32_t maxDatagramPayload)
{
(void) curTime;
nextSYNUpdate=0;
packetPairRecieptHistoryWriteIndex=0;
packetArrivalHistoryWriteIndex=0;
packetArrivalHistoryWriteCount=0;
RTT=UNSET_TIME_US;
// RTTVar=UNSET_TIME_US;
isInSlowStart=true;
NAKCount=1000;
AvgNAKNum=1;
DecInterval=1;
DecCount=0;
nextDatagramSequenceNumber=0;
lastPacketPairPacketArrivalTime=0;
lastPacketPairSequenceNumber=(DatagramSequenceNumberType)(const uint32_t)-1;
lastPacketArrivalTime=0;
CWND=CWND_MIN_THRESHOLD;
lastUpdateWindowSizeAndAck=0;
lastTransmitOfBAndAS=0;
ExpCount=1.0;
totalUserDataBytesSent=0;
oldestUnsentAck=0;
MAXIMUM_MTU_INCLUDING_UDP_HEADER=maxDatagramPayload;
CWND_MAX_THRESHOLD=RESEND_BUFFER_ARRAY_LENGTH;
#if CC_TIME_TYPE_BYTES==4
const BytesPerMicrosecond DEFAULT_TRANSFER_RATE=(BytesPerMicrosecond) 3.6;
#else
const BytesPerMicrosecond DEFAULT_TRANSFER_RATE=(BytesPerMicrosecond) .0036;
#endif
#if CC_TIME_TYPE_BYTES==4
lastRttOnIncreaseSendRate=1000;
#else
lastRttOnIncreaseSendRate=1000000;
#endif
nextCongestionControlBlock=0;
lastRtt=0;
// B=DEFAULT_TRANSFER_RATE;
AS=UNDEFINED_TRANSFER_RATE;
const MicrosecondsPerByte DEFAULT_BYTE_INTERVAL=(MicrosecondsPerByte) (1.0/DEFAULT_TRANSFER_RATE);
SND=DEFAULT_BYTE_INTERVAL;
expectedNextSequenceNumber=0;
sendBAndASCount=0;
packetArrivalHistoryContinuousGapsIndex=0;
//packetPairRecipetHistoryGapsIndex=0;
hasWrittenToPacketPairReceiptHistory=false;
InitPacketArrivalHistory();
estimatedLinkCapacityBytesPerSecond=0;
bytesCanSendThisTick=0;
hadPacketlossThisBlock=false;
pingsLastInterval.Clear(__FILE__,__LINE__);
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::SetMTU(uint32_t bytes)
{
MAXIMUM_MTU_INCLUDING_UDP_HEADER=bytes;
}
// ----------------------------------------------------------------------------------------------------------------------------
uint32_t CCRakNetUDT::GetMTU(void) const
{
return MAXIMUM_MTU_INCLUDING_UDP_HEADER;
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::Update(CCTimeType curTime, bool hasDataToSendOrResend)
{
(void) hasDataToSendOrResend;
(void) curTime;
return;
// I suspect this is causing major lag
/*
if (hasDataToSendOrResend==false)
halveSNDOnNoDataTime=0;
else if (halveSNDOnNoDataTime==0)
{
UpdateHalveSNDOnNoDataTime(curTime);
ExpCount=1.0;
}
// If you send, and get no data at all from that time to RTO, then halve send rate7
if (HasHalveSNDOnNoDataTimeElapsed(curTime))
{
/// 2000 bytes per second
/// 0.0005 seconds per byte
/// 0.5 milliseconds per byte
/// 500 microseconds per byte
// printf("No incoming data, halving send rate\n");
SND*=2.0;
CapMinSnd(_FILE_AND_LINE_);
ExpCount+=1.0;
if (ExpCount>8.0)
ExpCount=8.0;
UpdateHalveSNDOnNoDataTime(curTime);
}
*/
}
// ----------------------------------------------------------------------------------------------------------------------------
int CCRakNetUDT::GetRetransmissionBandwidth(CCTimeType curTime, CCTimeType timeSinceLastTick, uint32_t unacknowledgedBytes, bool isContinuousSend)
{
(void) curTime;
if (isInSlowStart)
{
uint32_t CWNDLimit = (uint32_t) (CWND*MAXIMUM_MTU_INCLUDING_UDP_HEADER);
return CWNDLimit;
}
return GetTransmissionBandwidth(curTime,timeSinceLastTick,unacknowledgedBytes,isContinuousSend);
}
// ----------------------------------------------------------------------------------------------------------------------------
int CCRakNetUDT::GetTransmissionBandwidth(CCTimeType curTime, CCTimeType timeSinceLastTick, uint32_t unacknowledgedBytes, bool isContinuousSend)
{
(void) curTime;
if (isInSlowStart)
{
uint32_t CWNDLimit = (uint32_t) (CWND*MAXIMUM_MTU_INCLUDING_UDP_HEADER-unacknowledgedBytes);
return CWNDLimit;
}
if (bytesCanSendThisTick>0)
bytesCanSendThisTick=0;
#if CC_TIME_TYPE_BYTES==4
if (isContinuousSend==false && timeSinceLastTick>100)
timeSinceLastTick=100;
#else
if (isContinuousSend==false && timeSinceLastTick>100000)
timeSinceLastTick=100000;
#endif
bytesCanSendThisTick=(int)((double)timeSinceLastTick*((double)1.0/SND)+(double)bytesCanSendThisTick);
if (bytesCanSendThisTick>0)
return bytesCanSendThisTick;
return 0;
}
uint64_t CCRakNetUDT::GetBytesPerSecondLimitByCongestionControl(void) const
{
if (isInSlowStart)
return 0;
#if CC_TIME_TYPE_BYTES==4
return (uint64_t) ((double)1.0/(SND*1000.0));
#else
return (uint64_t) ((double)1.0/(SND*1000000.0));
#endif
}
// ----------------------------------------------------------------------------------------------------------------------------
bool CCRakNetUDT::ShouldSendACKs(CCTimeType curTime, CCTimeType estimatedTimeToNextTick)
{
CCTimeType rto = GetSenderRTOForACK();
// iphone crashes on comparison between double and int64 http://www.jenkinssoftware.com/forum/index.php?topic=2717.0
if (rto==static_cast<double>(UNSET_TIME_US))
{
// Unknown how long until the remote system will retransmit, so better send right away
return true;
}
// CCTimeType remoteRetransmitTime=oldestUnsentAck+rto-RTT*.5;
// CCTimeType ackArrivalTimeIfWeDelay=RTT*.5+estimatedTimeToNextTick+curTime;
// return ackArrivalTimeIfWeDelay<remoteRetransmitTime;
// Simplified equation
// GU: At least one ACK should be sent per SYN, otherwise your protocol will increase slower.
return curTime >= oldestUnsentAck + SYN ||
estimatedTimeToNextTick+curTime < oldestUnsentAck+rto-RTT;
}
// ----------------------------------------------------------------------------------------------------------------------------
DatagramSequenceNumberType CCRakNetUDT::GetNextDatagramSequenceNumber(void)
{
return nextDatagramSequenceNumber;
}
// ----------------------------------------------------------------------------------------------------------------------------
DatagramSequenceNumberType CCRakNetUDT::GetAndIncrementNextDatagramSequenceNumber(void)
{
DatagramSequenceNumberType dsnt=nextDatagramSequenceNumber;
nextDatagramSequenceNumber++;
return dsnt;
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::OnSendBytes(CCTimeType curTime, uint32_t numBytes)
{
(void) curTime;
totalUserDataBytesSent+=numBytes;
if (isInSlowStart==false)
bytesCanSendThisTick-=numBytes;
}
// ****************************************************** PROTECTED METHODS ******************************************************
void CCRakNetUDT::SetNextSYNUpdate(CCTimeType currentTime)
{
nextSYNUpdate+=SYN;
if (nextSYNUpdate < currentTime)
nextSYNUpdate=currentTime+SYN;
}
// ----------------------------------------------------------------------------------------------------------------------------
BytesPerMicrosecond CCRakNetUDT::ReceiverCalculateDataArrivalRate(CCTimeType curTime) const
{
(void) curTime;
// Not an instantaneous measurement
/*
if (continuousBytesReceivedStartTime!=0 && curTime>continuousBytesReceivedStartTime)
{
#if CC_TIME_TYPE_BYTES==4
const CCTimeType threshold=100;
#else
const CCTimeType threshold=100000;
#endif
if (curTime-continuousBytesReceivedStartTime>threshold)
return (BytesPerMicrosecond) continuousBytesReceived/(BytesPerMicrosecond) (curTime-continuousBytesReceivedStartTime);
}
return UNDEFINED_TRANSFER_RATE;
*/
if (packetArrivalHistoryWriteCount<CC_RAKNET_UDT_PACKET_HISTORY_LENGTH)
return UNDEFINED_TRANSFER_RATE;
BytesPerMicrosecond median = ReceiverCalculateDataArrivalRateMedian();
int i;
const BytesPerMicrosecond oneEighthMedian=median*(1.0/8.0);
const BytesPerMicrosecond eightTimesMedian=median*8.0f;
BytesPerMicrosecond medianListLength=0.0;
BytesPerMicrosecond sum=0.0;
// Find average of acceptedMedianValues
for (i=0; i < CC_RAKNET_UDT_PACKET_HISTORY_LENGTH; i++)
{
if (packetArrivalHistory[i]>=oneEighthMedian &&
packetArrivalHistory[i]<eightTimesMedian)
{
medianListLength=medianListLength+1.0;
sum+=packetArrivalHistory[i];
}
}
if (medianListLength==0.0)
return UNDEFINED_TRANSFER_RATE;
return sum/medianListLength;
}
// ----------------------------------------------------------------------------------------------------------------------------
BytesPerMicrosecond CCRakNetUDT::ReceiverCalculateDataArrivalRateMedian(void) const
{
return CalculateListMedianRecursive(packetArrivalHistory, CC_RAKNET_UDT_PACKET_HISTORY_LENGTH, 0, 0);
}
// ----------------------------------------------------------------------------------------------------------------------------
BytesPerMicrosecond CCRakNetUDT::CalculateListMedianRecursive(const BytesPerMicrosecond inputList[CC_RAKNET_UDT_PACKET_HISTORY_LENGTH], int inputListLength, int lessThanSum, int greaterThanSum)
{
BytesPerMicrosecond lessThanMedian[CC_RAKNET_UDT_PACKET_HISTORY_LENGTH], greaterThanMedian[CC_RAKNET_UDT_PACKET_HISTORY_LENGTH];
int lessThanMedianListLength=0, greaterThanMedianListLength=0;
BytesPerMicrosecond median=inputList[0];
int i;
for (i=1; i < inputListLength; i++)
{
// If same value, spread among lists evenly
if (inputList[i]<median || ((i&1)==0 && inputList[i]==median))
lessThanMedian[lessThanMedianListLength++]=inputList[i];
else
greaterThanMedian[greaterThanMedianListLength++]=inputList[i];
}
RakAssert(CC_RAKNET_UDT_PACKET_HISTORY_LENGTH%2==0);
if (lessThanMedianListLength+lessThanSum==greaterThanMedianListLength+greaterThanSum+1 ||
lessThanMedianListLength+lessThanSum==greaterThanMedianListLength+greaterThanSum-1)
return median;
if (lessThanMedianListLength+lessThanSum < greaterThanMedianListLength+greaterThanSum)
{
lessThanMedian[lessThanMedianListLength++]=median;
return CalculateListMedianRecursive(greaterThanMedian, greaterThanMedianListLength, lessThanMedianListLength+lessThanSum, greaterThanSum);
}
else
{
greaterThanMedian[greaterThanMedianListLength++]=median;
return CalculateListMedianRecursive(lessThanMedian, lessThanMedianListLength, lessThanSum, greaterThanMedianListLength+greaterThanSum);
}
}
// ----------------------------------------------------------------------------------------------------------------------------
bool CCRakNetUDT::GreaterThan(DatagramSequenceNumberType a, DatagramSequenceNumberType b)
{
// a > b?
const DatagramSequenceNumberType halfSpan =(DatagramSequenceNumberType) (((DatagramSequenceNumberType)(const uint32_t)-1)/(DatagramSequenceNumberType)2);
return b!=a && b-a>halfSpan;
}
// ----------------------------------------------------------------------------------------------------------------------------
bool CCRakNetUDT::LessThan(DatagramSequenceNumberType a, DatagramSequenceNumberType b)
{
// a < b?
const DatagramSequenceNumberType halfSpan = ((DatagramSequenceNumberType)(const uint32_t)-1)/(DatagramSequenceNumberType)2;
return b!=a && b-a<halfSpan;
}
// ----------------------------------------------------------------------------------------------------------------------------
CCTimeType CCRakNetUDT::GetSenderRTOForACK(void) const
{
if (RTT==UNSET_TIME_US)
return (CCTimeType) UNSET_TIME_US;
double RTTVar = maxRTT-minRTT;
return (CCTimeType)(RTT + RTTVarMultiple * RTTVar + SYN);
}
// ----------------------------------------------------------------------------------------------------------------------------
CCTimeType CCRakNetUDT::GetRTOForRetransmission(void) const
{
#if CC_TIME_TYPE_BYTES==4
const CCTimeType maxThreshold=10000;
const CCTimeType minThreshold=100;
#else
const CCTimeType maxThreshold=1000000;
const CCTimeType minThreshold=100000;
#endif
if (RTT==UNSET_TIME_US)
{
return (CCTimeType) maxThreshold;
}
CCTimeType ret = lastRttOnIncreaseSendRate*2;
if (ret<minThreshold)
return minThreshold;
if (ret>maxThreshold)
return maxThreshold;
return ret;
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::OnResend(CCTimeType curTime)
{
(void) curTime;
if (isInSlowStart)
{
if (AS!=UNDEFINED_TRANSFER_RATE)
EndSlowStart();
return;
}
if (hadPacketlossThisBlock==false)
{
// Logging
// printf("Sending SLOWER due to Resend, Rate=%f MBPS. Rtt=%i\n", GetLocalSendRate(), lastRtt );
IncreaseTimeBetweenSends();
hadPacketlossThisBlock=true;
}
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::OnNAK(CCTimeType curTime, DatagramSequenceNumberType nakSequenceNumber)
{
(void) nakSequenceNumber;
(void) curTime;
if (isInSlowStart)
{
if (AS!=UNDEFINED_TRANSFER_RATE)
EndSlowStart();
return;
}
if (hadPacketlossThisBlock==false)
{
// Logging
//printf("Sending SLOWER due to NAK, Rate=%f MBPS. Rtt=%i\n", GetLocalSendRate(), lastRtt );
if (pingsLastInterval.Size()>10)
{
for (int i=0; i < 10; i++)
printf("%i, ", pingsLastInterval[pingsLastInterval.Size()-1-i]/1000);
}
printf("\n");
IncreaseTimeBetweenSends();
hadPacketlossThisBlock=true;
}
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::EndSlowStart(void)
{
RakAssert(isInSlowStart==true);
RakAssert(AS!=UNDEFINED_TRANSFER_RATE);
// This overestimates
estimatedLinkCapacityBytesPerSecond=AS * 1000000.0;
isInSlowStart=false;
SND=1.0/AS;
CapMinSnd(_FILE_AND_LINE_);
// printf("ENDING SLOW START\n");
#if CC_TIME_TYPE_BYTES==4
// printf("Initial SND=%f Kilobytes per second\n", 1.0/SND);
#else
// printf("Initial SND=%f Megabytes per second\n", 1.0/SND);
#endif
if (SND > .1)
PrintLowBandwidthWarning();
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::OnGotPacketPair(DatagramSequenceNumberType datagramSequenceNumber, uint32_t sizeInBytes, CCTimeType curTime)
{
(void) datagramSequenceNumber;
(void) sizeInBytes;
(void) curTime;
}
// ----------------------------------------------------------------------------------------------------------------------------
bool CCRakNetUDT::OnGotPacket(DatagramSequenceNumberType datagramSequenceNumber, bool isContinuousSend, CCTimeType curTime, uint32_t sizeInBytes, uint32_t *skippedMessageCount)
{
CC_DEBUG_PRINTF_2("R%i ",datagramSequenceNumber.val);
if (datagramSequenceNumber==expectedNextSequenceNumber)
{
*skippedMessageCount=0;
expectedNextSequenceNumber=datagramSequenceNumber+(DatagramSequenceNumberType)1;
}
else if (GreaterThan(datagramSequenceNumber, expectedNextSequenceNumber))
{
*skippedMessageCount=datagramSequenceNumber-expectedNextSequenceNumber;
// Sanity check, just use timeout resend if this was really valid
if (*skippedMessageCount>1000)
{
// During testing, the nat punchthrough server got 51200 on the first packet. I have no idea where this comes from, but has happened twice
if (*skippedMessageCount>(uint32_t)50000)
return false;
*skippedMessageCount=1000;
}
expectedNextSequenceNumber=datagramSequenceNumber+(DatagramSequenceNumberType)1;
}
else
{
*skippedMessageCount=0;
}
if (curTime>lastPacketArrivalTime)
{
CCTimeType interval = curTime-lastPacketArrivalTime;
// printf("Packet arrival gap is %I64u\n", (interval));
if (isContinuousSend)
{
continuousBytesReceived+=sizeInBytes;
if (continuousBytesReceivedStartTime==0)
continuousBytesReceivedStartTime=lastPacketArrivalTime;
mostRecentPacketArrivalHistory=(BytesPerMicrosecond)sizeInBytes/(BytesPerMicrosecond)interval;
// if (mostRecentPacketArrivalHistory < (BytesPerMicrosecond)0.0035)
// {
// printf("%s:%i LIKELY BUG: Calculated packetArrivalHistory is below 28.8 Kbps modem\nReport to rakkar@jenkinssoftware.com with file and line number\n", _FILE_AND_LINE_);
// }
packetArrivalHistoryContinuousGaps[packetArrivalHistoryContinuousGapsIndex++]=(int) interval;
packetArrivalHistoryContinuousGapsIndex&=(CC_RAKNET_UDT_PACKET_HISTORY_LENGTH-1);
packetArrivalHistoryWriteCount++;
packetArrivalHistory[packetArrivalHistoryWriteIndex++]=mostRecentPacketArrivalHistory;
// Wrap to 0 at the end of the range
// Assumes power of 2 for CC_RAKNET_UDT_PACKET_HISTORY_LENGTH
packetArrivalHistoryWriteIndex&=(CC_RAKNET_UDT_PACKET_HISTORY_LENGTH-1);
}
else
{
continuousBytesReceivedStartTime=0;
continuousBytesReceived=0;
}
lastPacketArrivalTime=curTime;
}
return true;
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::OnAck(CCTimeType curTime, CCTimeType rtt, bool hasBAndAS, BytesPerMicrosecond _B, BytesPerMicrosecond _AS, double totalUserDataBytesAcked, bool isContinuousSend, DatagramSequenceNumberType sequenceNumber )
{
#if CC_TIME_TYPE_BYTES==4
RakAssert(rtt < 10000);
#else
RakAssert(rtt < 10000000);
#endif
(void) _B;
if (hasBAndAS)
{
/// RakAssert(_B!=UNDEFINED_TRANSFER_RATE && _AS!=UNDEFINED_TRANSFER_RATE);
// B=B * .875 + _B * .125;
// AS is packet arrival rate
RakAssert(_AS!=UNDEFINED_TRANSFER_RATE);
AS=_AS;
CC_DEBUG_PRINTF_4("ArrivalRate=%f linkCap=%f incomingLinkCap=%f\n", _AS,B,_B);
}
if (oldestUnsentAck==0)
oldestUnsentAck=curTime;
if (isInSlowStart==true)
{
nextCongestionControlBlock=nextDatagramSequenceNumber;
lastRttOnIncreaseSendRate=rtt;
UpdateWindowSizeAndAckOnAckPreSlowStart(totalUserDataBytesAcked);
}
else
{
UpdateWindowSizeAndAckOnAckPerSyn(curTime, rtt, isContinuousSend, sequenceNumber);
}
lastUpdateWindowSizeAndAck=curTime;
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::OnSendAckGetBAndAS(CCTimeType curTime, bool *hasBAndAS, BytesPerMicrosecond *_B, BytesPerMicrosecond *_AS)
{
if (curTime>lastTransmitOfBAndAS+SYN)
{
*_B=0;
*_AS=ReceiverCalculateDataArrivalRate(curTime);
if (*_AS==UNDEFINED_TRANSFER_RATE)
{
*hasBAndAS=false;
}
else
{
*hasBAndAS=true;
}
}
else
{
*hasBAndAS=false;
}
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::OnSendAck(CCTimeType curTime, uint32_t numBytes)
{
(void) numBytes;
(void) curTime;
// This is not accounted for on the remote system, and thus causes bandwidth to be underutilized
//UpdateNextAllowedSend(curTime, numBytes+UDP_HEADER_SIZE);
oldestUnsentAck=0;
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::OnSendNACK(CCTimeType curTime, uint32_t numBytes)
{
(void) numBytes;
(void) curTime;
// This is not accounted for on the remote system, and thus causes bandwidth to be underutilized
// UpdateNextAllowedSend(curTime, numBytes+UDP_HEADER_SIZE);
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::UpdateWindowSizeAndAckOnAckPreSlowStart(double totalUserDataBytesAcked)
{
// During slow start, max window size is the number of full packets that have been sent out
// CWND=(double) ((double)totalUserDataBytesSent/(double)MAXIMUM_MTU_INCLUDING_UDP_HEADER);
CC_DEBUG_PRINTF_3("CWND increasing from %f to %f\n", CWND, (double) ((double)totalUserDataBytesAcked/(double)MAXIMUM_MTU_INCLUDING_UDP_HEADER));
CWND=(double) ((double)totalUserDataBytesAcked/(double)MAXIMUM_MTU_INCLUDING_UDP_HEADER);
if (CWND>=CWND_MAX_THRESHOLD)
{
CWND=CWND_MAX_THRESHOLD;
if (AS!=UNDEFINED_TRANSFER_RATE)
EndSlowStart();
}
if (CWND<CWND_MIN_THRESHOLD)
CWND=CWND_MIN_THRESHOLD;
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::UpdateWindowSizeAndAckOnAckPerSyn(CCTimeType curTime, CCTimeType rtt, bool isContinuousSend, DatagramSequenceNumberType sequenceNumber)
{
(void) curTime;
(void) sequenceNumber;
if (isContinuousSend==false)
{
nextCongestionControlBlock=nextDatagramSequenceNumber;
pingsLastInterval.Clear(__FILE__,__LINE__);
return;
}
pingsLastInterval.Push(rtt,__FILE__,__LINE__);
static const int intervalSize=33; // Should be odd
if (pingsLastInterval.Size()>intervalSize)
pingsLastInterval.Pop();
if (GreaterThan(sequenceNumber, nextCongestionControlBlock) &&
sequenceNumber-nextCongestionControlBlock>=intervalSize &&
pingsLastInterval.Size()==intervalSize)
{
double slopeSum=0.0;
double average=(double) pingsLastInterval[0];
int sampleSize=pingsLastInterval.Size();
for (int i=1; i < sampleSize; i++)
{
slopeSum+=(double)pingsLastInterval[i]-(double)pingsLastInterval[i-1];
average+=pingsLastInterval[i];
}
average/=sampleSize;
if (hadPacketlossThisBlock==true)
{
}
else if (slopeSum < -.10*average)
{
// Logging
//printf("Ping dropping. slope=%f%%. Rate=%f MBPS. Rtt=%i\n", 100.0*slopeSum/average, GetLocalSendRate(), rtt );
}
else if (slopeSum > .10*average)
{
// Logging
//printf("Ping rising. slope=%f%%. Rate=%f MBPS. Rtt=%i\n", 100.0*slopeSum/average, GetLocalSendRate(), rtt );
IncreaseTimeBetweenSends();
}
else
{
// Logging
//printf("Ping stable. slope=%f%%. Rate=%f MBPS. Rtt=%i\n", 100.0*slopeSum/average, GetLocalSendRate(), rtt );
// No packetloss over time threshhold, and rtt decreased, so send faster
lastRttOnIncreaseSendRate=rtt;
DecreaseTimeBetweenSends();
}
pingsLastInterval.Clear(__FILE__,__LINE__);
hadPacketlossThisBlock=false;
nextCongestionControlBlock=nextDatagramSequenceNumber;
}
lastRtt=rtt;
}
// ----------------------------------------------------------------------------------------------------------------------------
double CCRakNetUDT::BytesPerMicrosecondToPacketsPerMillisecond(BytesPerMicrosecond in)
{
#if CC_TIME_TYPE_BYTES==4
const BytesPerMicrosecond factor = 1.0 / (BytesPerMicrosecond) MAXIMUM_MTU_INCLUDING_UDP_HEADER;
#else
const BytesPerMicrosecond factor = 1000.0 / (BytesPerMicrosecond) MAXIMUM_MTU_INCLUDING_UDP_HEADER;
#endif
return in * factor;
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::InitPacketArrivalHistory(void)
{
unsigned int i;
for (i=0; i < CC_RAKNET_UDT_PACKET_HISTORY_LENGTH; i++)
{
packetArrivalHistory[i]=UNDEFINED_TRANSFER_RATE;
packetArrivalHistoryContinuousGaps[i]=0;
}
packetArrivalHistoryWriteCount=0;
continuousBytesReceived=0;
continuousBytesReceivedStartTime=0;
}
// ----------------------------------------------------------------------------------------------------------------------------
void CCRakNetUDT::PrintLowBandwidthWarning(void)
{
/*
printf("\n-------LOW BANDWIDTH -----\n");
if (isInSlowStart==false)
printf("SND=%f Megabytes per second\n", 1.0/SND);
printf("Window size=%f\n", CWND);
printf("Pipe from packet pair = %f megabytes per second\n", B);
printf("RTT=%f milliseconds\n", RTT/1000.0);
printf("RTT Variance=%f milliseconds\n", RTTVar/1000.0);
printf("Retransmission=%i milliseconds\n", GetRTOForRetransmission()/1000);
printf("Packet arrival rate on the remote system=%f megabytes per second\n", AS);
printf("Packet arrival rate on our system=%f megabytes per second\n", ReceiverCalculateDataArrivalRate());
printf("isInSlowStart=%i\n", isInSlowStart);
printf("---------------\n");
*/
}
BytesPerMicrosecond CCRakNetUDT::GetLocalReceiveRate(CCTimeType currentTime) const
{
return ReceiverCalculateDataArrivalRate(currentTime);
}
double CCRakNetUDT::GetRTT(void) const
{
if (RTT==UNSET_TIME_US)
return 0.0;
return RTT;
}
void CCRakNetUDT::CapMinSnd(const char *file, int line)
{
(void) file;
(void) line;
if (SND > 500)
{
SND=500;
CC_DEBUG_PRINTF_3("%s:%i LIKELY BUG: SND has gotten above 500 microseconds between messages (28.8 modem)\nReport to rakkar@jenkinssoftware.com with file and line number\n", file, line);
}
}
void CCRakNetUDT::IncreaseTimeBetweenSends(void)
{
// In order to converge, bigger numbers have to increase slower and decrease faster
// SND==500 then increment is .02
// SND==0 then increment is near 0
// (SND+1.0) brings it to the range of 1 to 501
// Square the number, which is the range of 1 to 251001
// Divide by 251001, which is the range of 1/251001 to 1
double increment;
increment = .02 * ((SND+1.0) * (SND+1.0)) / (501.0*501.0) ;
// SND=500 then increment=.02
// SND=0 then increment=near 0
SND*=(1.02 - increment);
// SND=0 then fast increase, slow decrease
// SND=500 then slow increase, fast decrease
CapMinSnd(__FILE__,__LINE__);
}
void CCRakNetUDT::DecreaseTimeBetweenSends(void)
{
double increment;
increment = .01 * ((SND+1.0) * (SND+1.0)) / (501.0*501.0) ;
// SND=500 then increment=.01
// SND=0 then increment=near 0
SND*=(.99 - increment);
}
/*
void CCRakNetUDT::SetTimeBetweenSendsLimit(unsigned int bitsPerSecond)
{
// bitsPerSecond / 1000000 = bitsPerMicrosecond
// bitsPerMicrosecond / 8 = BytesPerMicrosecond
// 1 / BytesPerMicrosecond = MicrosecondsPerByte
// 1 / ( (bitsPerSecond / 1000000) / 8 ) =
// 1 / (bitsPerSecond / 8000000) =
// 8000000 / bitsPerSecond
#if CC_TIME_TYPE_BYTES==4
MicrosecondsPerByte limit = (MicrosecondsPerByte) 8000 / (MicrosecondsPerByte)bitsPerSecond;
#else
MicrosecondsPerByte limit = (MicrosecondsPerByte) 8000000 / (MicrosecondsPerByte)bitsPerSecond;
#endif
if (limit > SND)
SND=limit;
}
*/
#endif