Added auto-escalation to multipath if both peers support it. Improved QoS/ACK tracking. Related bug fixes

This commit is contained in:
Joseph Henry 2018-06-01 18:03:59 -07:00
parent 46a7a2be2e
commit 91a22a686a
5 changed files with 200 additions and 112 deletions

View file

@ -40,6 +40,7 @@
#include "AtomicCounter.hpp"
#include "Utils.hpp"
#include "RingBuffer.hpp"
#include "Packet.hpp"
#include "../osdep/Phy.hpp"
@ -105,9 +106,11 @@ public:
_lastAck(0),
_lastThroughputEstimation(0),
_lastQoSMeasurement(0),
_lastQoSRecordPurge(0),
_unackedBytes(0),
_expectingAckAsOf(0),
_packetsReceivedSinceLastAck(0),
_packetsReceivedSinceLastQoS(0),
_meanThroughput(0.0),
_maxLifetimeThroughput(0),
_bytesAckedSinceLastThroughputEstimation(0),
@ -133,9 +136,11 @@ public:
_lastAck(0),
_lastThroughputEstimation(0),
_lastQoSMeasurement(0),
_lastQoSRecordPurge(0),
_unackedBytes(0),
_expectingAckAsOf(0),
_packetsReceivedSinceLastAck(0),
_packetsReceivedSinceLastQoS(0),
_meanThroughput(0.0),
_maxLifetimeThroughput(0),
_bytesAckedSinceLastThroughputEstimation(0),
@ -147,6 +152,7 @@ public:
_lastComputedRelativeQuality(0)
{
prepareBuffers();
_phy->getIfName((PhySocket *)((uintptr_t)_localSocket), _ifname, 16);
}
~Path()
@ -295,17 +301,52 @@ public:
}
/**
* Take note that we're expecting a VERB_ACK on this path as of a specific time
* Record statistics on outgoing packets. Used later to estimate QoS metrics.
*
* @param now Current time
* @param packetId ID of the packet
* @param payloadLength Number of bytes we're is expecting a reply to
* @param packetId ID of packet
* @param payloadLength Length of payload
* @param verb Packet verb
*/
inline void expectingAck(int64_t now, int64_t packetId, uint16_t payloadLength)
inline void recordOutgoingPacket(int64_t now, int64_t packetId, uint16_t payloadLength, Packet::Verb verb)
{
_expectingAckAsOf = ackAge(now) > ZT_PATH_ACK_INTERVAL ? _expectingAckAsOf : now;
_unackedBytes += payloadLength;
_outgoingPacketRecords[packetId] = now;
Mutex::Lock _l(_statistics_m);
if (verb == Packet::VERB_FRAME || verb == Packet::VERB_EXT_FRAME) {
if (packetId % 2 == 0) { // even -> use for ACK
_unackedBytes += payloadLength;
// Take note that we're expecting a VERB_ACK on this path as of a specific time
_expectingAckAsOf = ackAge(now) > ZT_PATH_ACK_INTERVAL ? _expectingAckAsOf : now;
}
else { // odd -> use for QoS
if (_outQoSRecords.size() < ZT_PATH_MAX_OUTSTANDING_QOS_RECORDS) {
_outQoSRecords[packetId] = now;
}
}
}
}
/**
* Record statistics on incoming packets. Used later to estimate QoS metrics.
*
* @param now Current time
* @param packetId ID of packet
* @param payloadLength Length of payload
* @param verb Packet verb
*/
inline void recordIncomingPacket(int64_t now, int64_t packetId, uint16_t payloadLength, Packet::Verb verb)
{
Mutex::Lock _l(_statistics_m);
if (verb == Packet::VERB_FRAME || verb == Packet::VERB_EXT_FRAME) {
if (packetId % 2 == 0) { // even -> use for ACK
_inACKRecords[packetId] = payloadLength;
_packetsReceivedSinceLastAck++;
}
else { // odd -> use for QoS
_inQoSRecords[packetId] = now;
_packetsReceivedSinceLastQoS++;
}
_packetValiditySamples->push(true);
}
}
/**
@ -335,9 +376,12 @@ public:
*/
inline int32_t bytesToAck()
{
Mutex::Lock _l(_statistics_m);
int32_t bytesToAck = 0;
for (int i=0; i<_packetsReceivedSinceLastAck; i++) {
bytesToAck += _recorded_len[i];
std::map<uint64_t,uint16_t>::iterator it = _inACKRecords.begin();
while (it != _inACKRecords.end()) {
bytesToAck += it->second;
it++;
}
return bytesToAck;
}
@ -357,9 +401,8 @@ public:
*/
inline void sentAck(int64_t now)
{
memset(_recorded_id, 0, sizeof(_recorded_id));
memset(_recorded_ts, 0, sizeof(_recorded_ts));
memset(_recorded_len, 0, sizeof(_recorded_len));
Mutex::Lock _l(_statistics_m);
_inACKRecords.clear();
_packetsReceivedSinceLastAck = 0;
_lastAck = now;
}
@ -373,17 +416,19 @@ public:
* @param rx_id table of packet IDs
* @param rx_ts table of holding times
*/
inline void receivedQoS(int64_t now, int count, uint64_t *rx_id, uint8_t *rx_ts)
inline void receivedQoS(int64_t now, int count, uint64_t *rx_id, uint16_t *rx_ts)
{
Mutex::Lock _l(_statistics_m);
// Look up egress times and compute latency values for each record
std::map<uint64_t,uint64_t>::iterator it;
for (int j=0; j<count; j++) {
std::map<uint64_t,uint64_t>::iterator it = _outgoingPacketRecords.find(rx_id[j]);
if (it != _outgoingPacketRecords.end()) {
it = _outQoSRecords.find(rx_id[j]);
if (it != _outQoSRecords.end()) {
uint16_t rtt = (uint16_t)(now - it->second);
uint16_t rtt_compensated = rtt - rx_ts[j];
float latency = rtt_compensated / 2.0;
updateLatency(latency, now);
_outgoingPacketRecords.erase(it);
_outQoSRecords.erase(it);
}
}
}
@ -397,15 +442,20 @@ public:
*/
inline int32_t generateQoSPacket(int64_t now, char *qosBuffer)
{
Mutex::Lock _l(_statistics_m);
int32_t len = 0;
for (int i=0; i<_packetsReceivedSinceLastAck; i++) {
uint64_t id = _recorded_id[i];
std::map<uint64_t,uint64_t>::iterator it = _inQoSRecords.begin();
int i=0;
while (i<_packetsReceivedSinceLastQoS && it != _inQoSRecords.end()) {
uint64_t id = it->first;
memcpy(qosBuffer, &id, sizeof(uint64_t));
qosBuffer+=sizeof(uint64_t);
uint8_t holdingTime = (uint8_t)(now - _recorded_ts[i]);
memcpy(qosBuffer, &holdingTime, sizeof(uint8_t));
qosBuffer+=sizeof(uint8_t);
len+=sizeof(uint64_t)+sizeof(uint8_t);
uint16_t holdingTime = (now - it->second);
memcpy(qosBuffer, &holdingTime, sizeof(uint16_t));
qosBuffer+=sizeof(uint16_t);
len+=sizeof(uint64_t)+sizeof(uint16_t);
_inQoSRecords.erase(it++);
i++;
}
return len;
}
@ -415,22 +465,9 @@ public:
*
* @param Current time
*/
inline void sentQoS(int64_t now) { _lastQoSMeasurement = now; }
/**
* Record statistics on incoming packets. Used later to estimate QoS.
*
* @param now Current time
* @param packetId
* @param payloadLength
*/
inline void recordIncomingPacket(int64_t now, int64_t packetId, int32_t payloadLength)
{
_recorded_ts[_packetsReceivedSinceLastAck] = now;
_recorded_id[_packetsReceivedSinceLastAck] = packetId;
_recorded_len[_packetsReceivedSinceLastAck] = payloadLength;
_packetsReceivedSinceLastAck++;
_packetValiditySamples->push(true);
inline void sentQoS(int64_t now) {
_packetsReceivedSinceLastQoS = 0;
_lastQoSMeasurement = now;
}
/**
@ -447,8 +484,8 @@ public:
* @return Whether a QoS (VERB_QOS_MEASUREMENT) packet needs to be emitted at this time
*/
inline bool needsToSendQoS(int64_t now) {
return ((_packetsReceivedSinceLastAck >= ZT_PATH_QOS_TABLE_SIZE) ||
((now - _lastQoSMeasurement) > ZT_PATH_QOS_INTERVAL)) && _packetsReceivedSinceLastAck;
return ((_packetsReceivedSinceLastQoS >= ZT_PATH_QOS_TABLE_SIZE) ||
((now - _lastQoSMeasurement) > ZT_PATH_QOS_INTERVAL)) && _packetsReceivedSinceLastQoS;
}
/**
@ -523,15 +560,16 @@ public:
inline char *getAddressString() { return _addrString; }
/**
* Compute and cache stability and performance metrics. The resultant stability coefficint is a measure of how "well behaved"
* Compute and cache stability and performance metrics. The resultant stability coefficient is a measure of how "well behaved"
* this path is. This figure is substantially different from (but required for the estimation of the path's overall "quality".
*
* @param now Current time
*/
inline void processBackgroundPathMeasurements(int64_t now, const int64_t peerId) {
Mutex::Lock _l(_statistics_m);
// Compute path stability
if (now - _lastPathQualityComputeTime > ZT_PATH_QUALITY_COMPUTE_INTERVAL) {
_lastPathQualityComputeTime = now;
_phy->getIfName((PhySocket *)((uintptr_t)_localSocket), _ifname, 16);
address().toString(_addrString);
_meanThroughput = _throughputSamples->mean();
_meanLatency = _latencySamples->mean();
@ -556,6 +594,17 @@ public:
_lastComputedStability *= 1 - _packetErrorRatio;
_qualitySamples->push(_lastComputedStability);
}
// Prevent QoS records from sticking around for too long
if (now - _lastQoSRecordPurge > ZT_PATH_QOS_RECORD_PURGE_INTERVAL)
{
std::map<uint64_t,uint64_t>::iterator it = _outQoSRecords.begin();
while (it != _outQoSRecords.end()) {
// Time since egress of tracked packet
if ((now - it->second) >= ZT_PATH_QOS_TIMEOUT) {
_outQoSRecords.erase(it++);
} else { it++; }
}
}
}
/**
@ -592,13 +641,12 @@ public:
_qualitySamples = new RingBuffer<float>(ZT_PATH_QUALITY_METRIC_WIN_SZ);
_packetValiditySamples = new RingBuffer<bool>(ZT_PATH_QUALITY_METRIC_WIN_SZ);
memset(_ifname, 0, 16);
memset(_recorded_id, 0, sizeof(_recorded_id));
memset(_recorded_ts, 0, sizeof(_recorded_ts));
memset(_recorded_len, 0, sizeof(_recorded_len));
memset(_addrString, 0, sizeof(_addrString));
}
private:
Mutex _statistics_m;
volatile int64_t _lastOut;
volatile int64_t _lastIn;
volatile int64_t _lastTrustEstablishedPacketReceived;
@ -609,19 +657,19 @@ private:
InetAddress::IpScope _ipScope; // memoize this since it's a computed value checked often
AtomicCounter __refCount;
uint64_t _recorded_id[ZT_PATH_QOS_TABLE_SIZE];
uint64_t _recorded_ts[ZT_PATH_QOS_TABLE_SIZE];
uint16_t _recorded_len[ZT_PATH_QOS_TABLE_SIZE];
std::map<uint64_t, uint64_t> _outgoingPacketRecords;
std::map<uint64_t, uint64_t> _outQoSRecords; // id:egress_time
std::map<uint64_t, uint64_t> _inQoSRecords; // id:now
std::map<uint64_t, uint16_t> _inACKRecords; // id:len
int64_t _lastAck;
int64_t _lastThroughputEstimation;
int64_t _lastQoSMeasurement;
int64_t _lastQoSRecordPurge;
int64_t _unackedBytes;
int64_t _expectingAckAsOf;
int16_t _packetsReceivedSinceLastAck;
int16_t _packetsReceivedSinceLastQoS;
float _meanThroughput;
uint64_t _maxLifetimeThroughput;