Added multipath field to zerotier-cli status output. Adjusted how path estimates are computed and cached

This commit is contained in:
Joseph Henry 2018-06-14 16:34:45 -07:00
parent f8005b88ad
commit 17fbb020e7
6 changed files with 169 additions and 47 deletions

View file

@ -111,15 +111,16 @@ public:
_expectingAckAsOf(0),
_packetsReceivedSinceLastAck(0),
_packetsReceivedSinceLastQoS(0),
_meanThroughput(0.0),
_maxLifetimeThroughput(0),
_lastComputedMeanThroughput(0),
_bytesAckedSinceLastThroughputEstimation(0),
_meanLatency(0.0),
_packetDelayVariance(0.0),
_packetErrorRatio(0.0),
_packetLossRatio(0),
_lastComputedMeanLatency(0.0),
_lastComputedPacketDelayVariance(0.0),
_lastComputedPacketErrorRatio(0.0),
_lastComputedPacketLossRatio(0),
_lastComputedStability(0.0),
_lastComputedRelativeQuality(0),
_lastComputedThroughputDistCoeff(0.0),
_lastAllocation(0.0)
{
prepareBuffers();
@ -142,15 +143,16 @@ public:
_expectingAckAsOf(0),
_packetsReceivedSinceLastAck(0),
_packetsReceivedSinceLastQoS(0),
_meanThroughput(0.0),
_maxLifetimeThroughput(0),
_lastComputedMeanThroughput(0),
_bytesAckedSinceLastThroughputEstimation(0),
_meanLatency(0.0),
_packetDelayVariance(0.0),
_packetErrorRatio(0.0),
_packetLossRatio(0),
_lastComputedMeanLatency(0.0),
_lastComputedPacketDelayVariance(0.0),
_lastComputedPacketErrorRatio(0.0),
_lastComputedPacketLossRatio(0),
_lastComputedStability(0.0),
_lastComputedRelativeQuality(0),
_lastComputedThroughputDistCoeff(0.0),
_lastAllocation(0.0)
{
prepareBuffers();
@ -162,9 +164,11 @@ public:
delete _throughputSamples;
delete _latencySamples;
delete _packetValiditySamples;
delete _throughputDisturbanceSamples;
_throughputSamples = NULL;
_latencySamples = NULL;
_packetValiditySamples = NULL;
_throughputDisturbanceSamples = NULL;
}
/**
@ -311,7 +315,7 @@ public:
inline void recordOutgoingPacket(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 (verb != Packet::VERB_ACK && verb != Packet::VERB_QOS_MEASUREMENT) {
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
@ -336,7 +340,7 @@ public:
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 (verb != Packet::VERB_ACK && verb != Packet::VERB_QOS_MEASUREMENT) {
if (packetId % 2 == 0) { // even -> use for ACK
_inACKRecords[packetId] = payloadLength;
_packetsReceivedSinceLastAck++;
@ -497,14 +501,14 @@ public:
inline int64_t ackAge(int64_t now) { return _expectingAckAsOf ? now - _expectingAckAsOf : 0; }
/**
* The maximum observed throughput for this path
* The maximum observed throughput (in bits/s) for this path
*/
inline uint64_t maxLifetimeThroughput() { return _maxLifetimeThroughput; }
/**
* @return The mean throughput (in bits/s) of this link
*/
inline float meanThroughput() { return _meanThroughput; }
inline uint64_t meanThroughput() { return _lastComputedMeanThroughput; }
/**
* Assign a new relative quality value for this path in the aggregate link
@ -543,22 +547,22 @@ public:
/**
* @return Packet delay variance
*/
inline float packetDelayVariance() { return _packetDelayVariance; }
inline float packetDelayVariance() { return _lastComputedPacketDelayVariance; }
/**
* @return Previously-computed mean latency
*/
inline float meanLatency() { return _meanLatency; }
inline float meanLatency() { return _lastComputedMeanLatency; }
/**
* @return Packet loss rate (PLR)
*/
inline float packetLossRatio() { return _packetLossRatio; }
inline float packetLossRatio() { return _lastComputedPacketLossRatio; }
/**
* @return Packet error ratio (PER)
*/
inline float packetErrorRatio() { return _packetErrorRatio; }
inline float packetErrorRatio() { return _lastComputedPacketErrorRatio; }
/**
* Record an invalid incoming packet. This packet failed MAC/compression/cipher checks and will now
@ -571,38 +575,46 @@ public:
*/
inline char *getAddressString() { return _addrString; }
/**
* @return The current throughput disturbance coefficient
*/
inline float throughputDisturbanceCoefficient() { return _lastComputedThroughputDistCoeff; }
/**
* 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) {
inline void processBackgroundPathMeasurements(int64_t now) {
if (now - _lastPathQualityComputeTime > ZT_PATH_QUALITY_COMPUTE_INTERVAL) {
Mutex::Lock _l(_statistics_m);
_lastPathQualityComputeTime = now;
address().toString(_addrString);
_meanThroughput = _throughputSamples->mean();
_meanLatency = _latencySamples->mean();
_packetDelayVariance = _latencySamples->stddev(); // Similar to "jitter" (SEE: RFC 3393, RFC 4689)
_lastComputedMeanLatency = _latencySamples->mean();
_lastComputedPacketDelayVariance = _latencySamples->stddev(); // Similar to "jitter" (SEE: RFC 3393, RFC 4689)
_lastComputedMeanThroughput = (uint64_t)_throughputSamples->mean();
// If no packet validity samples, assume PER==0
_packetErrorRatio = 1 - (_packetValiditySamples->count() ? _packetValiditySamples->mean() : 1);
_lastComputedPacketErrorRatio = 1 - (_packetValiditySamples->count() ? _packetValiditySamples->mean() : 1);
// Compute path stability
// Normalize measurements with wildly different ranges into a reasonable range
float normalized_pdv = Utils::normalize(_packetDelayVariance, 0, ZT_PATH_MAX_PDV, 0, 10);
float normalized_la = Utils::normalize(_meanLatency, 0, ZT_PATH_MAX_MEAN_LATENCY, 0, 10);
float normalized_pdv = Utils::normalize(_lastComputedPacketDelayVariance, 0, ZT_PATH_MAX_PDV, 0, 10);
float normalized_la = Utils::normalize(_lastComputedMeanLatency, 0, ZT_PATH_MAX_MEAN_LATENCY, 0, 10);
float throughput_cv = _throughputSamples->mean() > 0 ? _throughputSamples->stddev() / _throughputSamples->mean() : 1;
// Form an exponential cutoff and apply contribution weights
float pdv_contrib = exp((-1)*normalized_pdv) * ZT_PATH_CONTRIB_PDV;
float latency_contrib = exp((-1)*normalized_la) * ZT_PATH_CONTRIB_LATENCY;
// Throughput Disturbance Coefficient
float throughput_disturbance_contrib = exp((-1)*throughput_cv) * ZT_PATH_CONTRIB_THROUGHPUT_DISTURBANCE;
_throughputDisturbanceSamples->push(throughput_cv);
_lastComputedThroughputDistCoeff = _throughputDisturbanceSamples->mean();
// Obey user-defined ignored contributions
pdv_contrib = ZT_PATH_CONTRIB_PDV > 0.0 ? pdv_contrib : 1;
latency_contrib = ZT_PATH_CONTRIB_LATENCY > 0.0 ? latency_contrib : 1;
throughput_disturbance_contrib = ZT_PATH_CONTRIB_THROUGHPUT_DISTURBANCE > 0.0 ? throughput_disturbance_contrib : 1;
// Compute the quality product
// Stability
_lastComputedStability = pdv_contrib + latency_contrib + throughput_disturbance_contrib;
_lastComputedStability *= 1 - _packetErrorRatio;
_lastComputedStability *= 1 - _lastComputedPacketErrorRatio;
// Prevent QoS records from sticking around for too long
std::map<uint64_t,uint64_t>::iterator it = _outQoSRecords.begin();
while (it != _outQoSRecords.end()) {
@ -646,6 +658,7 @@ public:
_throughputSamples = new RingBuffer<uint64_t>(ZT_PATH_QUALITY_METRIC_WIN_SZ);
_latencySamples = new RingBuffer<uint32_t>(ZT_PATH_QUALITY_METRIC_WIN_SZ);
_packetValiditySamples = new RingBuffer<bool>(ZT_PATH_QUALITY_METRIC_WIN_SZ);
_throughputDisturbanceSamples = new RingBuffer<float>(ZT_PATH_QUALITY_METRIC_WIN_SZ);
memset(_ifname, 0, 16);
memset(_addrString, 0, sizeof(_addrString));
}
@ -677,19 +690,20 @@ private:
int16_t _packetsReceivedSinceLastAck;
int16_t _packetsReceivedSinceLastQoS;
float _meanThroughput;
uint64_t _maxLifetimeThroughput;
uint64_t _lastComputedMeanThroughput;
uint64_t _bytesAckedSinceLastThroughputEstimation;
volatile float _meanLatency;
float _packetDelayVariance;
float _lastComputedMeanLatency;
float _lastComputedPacketDelayVariance;
float _packetErrorRatio;
float _packetLossRatio;
float _lastComputedPacketErrorRatio;
float _lastComputedPacketLossRatio;
// cached estimates
float _lastComputedStability;
float _lastComputedRelativeQuality;
float _lastComputedThroughputDistCoeff;
float _lastAllocation;
// cached human-readable strings for tracing purposes
@ -699,6 +713,7 @@ private:
RingBuffer<uint64_t> *_throughputSamples;
RingBuffer<uint32_t> *_latencySamples;
RingBuffer<bool> *_packetValiditySamples;
RingBuffer<float> *_throughputDisturbanceSamples;
};
} // namespace ZeroTier