package h2mux import ( "sync" "time" "github.com/golang-collections/collections/queue" log "github.com/sirupsen/logrus" ) // data points used to compute average receive window and send window size const ( // data points used to compute average receive window and send window size dataPoints = 100 // updateFreq is set to 1 sec so we can get inbound & outbound byes/sec updateFreq = time.Second ) type muxMetricsUpdater interface { // metrics returns the latest metrics metrics() *MuxerMetrics // run is a blocking call to start the event loop run(logger *log.Entry) error // updateRTTChan is called by muxReader to report new RTT measurements updateRTT(rtt *roundTripMeasurement) //updateReceiveWindowChan is called by muxReader and muxWriter when receiveWindow size is updated updateReceiveWindow(receiveWindow uint32) //updateSendWindowChan is called by muxReader and muxWriter when sendWindow size is updated updateSendWindow(sendWindow uint32) // updateInBoundBytesChan is called periodicallyby muxReader to report bytesRead updateInBoundBytes(inBoundBytes uint64) // updateOutBoundBytesChan is called periodically by muxWriter to report bytesWrote updateOutBoundBytes(outBoundBytes uint64) } type muxMetricsUpdaterImpl struct { // rttData keeps record of rtt, rttMin, rttMax and last measured time rttData *rttData // receiveWindowData keeps record of receive window measurement receiveWindowData *flowControlData // sendWindowData keeps record of send window measurement sendWindowData *flowControlData // inBoundRate is incoming bytes/sec inBoundRate *rate // outBoundRate is outgoing bytes/sec outBoundRate *rate // updateRTTChan is the channel to receive new RTT measurement updateRTTChan chan *roundTripMeasurement //updateReceiveWindowChan is the channel to receive updated receiveWindow size updateReceiveWindowChan chan uint32 //updateSendWindowChan is the channel to receive updated sendWindow size updateSendWindowChan chan uint32 // updateInBoundBytesChan us the channel to receive bytesRead updateInBoundBytesChan chan uint64 // updateOutBoundBytesChan us the channel to receive bytesWrote updateOutBoundBytesChan chan uint64 // shutdownC is to signal the muxerMetricsUpdater to shutdown abortChan <-chan struct{} compBytesBefore, compBytesAfter *AtomicCounter } type MuxerMetrics struct { RTT, RTTMin, RTTMax time.Duration ReceiveWindowAve, SendWindowAve float64 ReceiveWindowMin, ReceiveWindowMax, SendWindowMin, SendWindowMax uint32 InBoundRateCurr, InBoundRateMin, InBoundRateMax uint64 OutBoundRateCurr, OutBoundRateMin, OutBoundRateMax uint64 CompBytesBefore, CompBytesAfter *AtomicCounter } func (m *MuxerMetrics) CompRateAve() float64 { if m.CompBytesBefore.Value() == 0 { return 1. } return float64(m.CompBytesAfter.Value()) / float64(m.CompBytesBefore.Value()) } type roundTripMeasurement struct { receiveTime, sendTime time.Time } type rttData struct { rtt, rttMin, rttMax time.Duration lastMeasurementTime time.Time lock sync.RWMutex } type flowControlData struct { sum uint64 min, max uint32 queue *queue.Queue lock sync.RWMutex } type rate struct { curr uint64 min, max uint64 lock sync.RWMutex } func newMuxMetricsUpdater( abortChan <-chan struct{}, compBytesBefore, compBytesAfter *AtomicCounter, ) muxMetricsUpdater { updateRTTChan := make(chan *roundTripMeasurement, 1) updateReceiveWindowChan := make(chan uint32, 1) updateSendWindowChan := make(chan uint32, 1) updateInBoundBytesChan := make(chan uint64) updateOutBoundBytesChan := make(chan uint64) return &muxMetricsUpdaterImpl{ rttData: newRTTData(), receiveWindowData: newFlowControlData(), sendWindowData: newFlowControlData(), inBoundRate: newRate(), outBoundRate: newRate(), updateRTTChan: updateRTTChan, updateReceiveWindowChan: updateReceiveWindowChan, updateSendWindowChan: updateSendWindowChan, updateInBoundBytesChan: updateInBoundBytesChan, updateOutBoundBytesChan: updateOutBoundBytesChan, abortChan: abortChan, compBytesBefore: compBytesBefore, compBytesAfter: compBytesAfter, } } func (updater *muxMetricsUpdaterImpl) metrics() *MuxerMetrics { m := &MuxerMetrics{} m.RTT, m.RTTMin, m.RTTMax = updater.rttData.metrics() m.ReceiveWindowAve, m.ReceiveWindowMin, m.ReceiveWindowMax = updater.receiveWindowData.metrics() m.SendWindowAve, m.SendWindowMin, m.SendWindowMax = updater.sendWindowData.metrics() m.InBoundRateCurr, m.InBoundRateMin, m.InBoundRateMax = updater.inBoundRate.get() m.OutBoundRateCurr, m.OutBoundRateMin, m.OutBoundRateMax = updater.outBoundRate.get() m.CompBytesBefore, m.CompBytesAfter = updater.compBytesBefore, updater.compBytesAfter return m } func (updater *muxMetricsUpdaterImpl) run(parentLogger *log.Entry) error { logger := parentLogger.WithFields(log.Fields{ "subsystem": "mux", "dir": "metrics", }) defer logger.Debug("event loop finished") for { select { case <-updater.abortChan: logger.Infof("Stopping mux metrics updater") return nil case roundTripMeasurement := <-updater.updateRTTChan: go updater.rttData.update(roundTripMeasurement) logger.Debug("Update rtt") case receiveWindow := <-updater.updateReceiveWindowChan: go updater.receiveWindowData.update(receiveWindow) logger.Debug("Update receive window") case sendWindow := <-updater.updateSendWindowChan: go updater.sendWindowData.update(sendWindow) logger.Debug("Update send window") case inBoundBytes := <-updater.updateInBoundBytesChan: // inBoundBytes is bytes/sec because the update interval is 1 sec go updater.inBoundRate.update(inBoundBytes) logger.Debugf("Inbound bytes %d", inBoundBytes) case outBoundBytes := <-updater.updateOutBoundBytesChan: // outBoundBytes is bytes/sec because the update interval is 1 sec go updater.outBoundRate.update(outBoundBytes) logger.Debugf("Outbound bytes %d", outBoundBytes) } } } func (updater *muxMetricsUpdaterImpl) updateRTT(rtt *roundTripMeasurement) { select { case updater.updateRTTChan <- rtt: case <-updater.abortChan: } } func (updater *muxMetricsUpdaterImpl) updateReceiveWindow(receiveWindow uint32) { select { case updater.updateReceiveWindowChan <- receiveWindow: case <-updater.abortChan: } } func (updater *muxMetricsUpdaterImpl) updateSendWindow(sendWindow uint32) { select { case updater.updateSendWindowChan <- sendWindow: case <-updater.abortChan: } } func (updater *muxMetricsUpdaterImpl) updateInBoundBytes(inBoundBytes uint64) { select { case updater.updateInBoundBytesChan <- inBoundBytes: case <-updater.abortChan: } } func (updater *muxMetricsUpdaterImpl) updateOutBoundBytes(outBoundBytes uint64) { select { case updater.updateOutBoundBytesChan <- outBoundBytes: case <-updater.abortChan: } } func newRTTData() *rttData { return &rttData{} } func (r *rttData) update(measurement *roundTripMeasurement) { r.lock.Lock() defer r.lock.Unlock() // discard pings before lastMeasurementTime if r.lastMeasurementTime.After(measurement.sendTime) { return } r.lastMeasurementTime = measurement.sendTime r.rtt = measurement.receiveTime.Sub(measurement.sendTime) if r.rttMax < r.rtt { r.rttMax = r.rtt } if r.rttMin == 0 || r.rttMin > r.rtt { r.rttMin = r.rtt } } func (r *rttData) metrics() (rtt, rttMin, rttMax time.Duration) { r.lock.RLock() defer r.lock.RUnlock() return r.rtt, r.rttMin, r.rttMax } func newFlowControlData() *flowControlData { return &flowControlData{queue: queue.New()} } func (f *flowControlData) update(measurement uint32) { f.lock.Lock() defer f.lock.Unlock() var firstItem uint32 // store new data into queue, remove oldest data if queue is full f.queue.Enqueue(measurement) if f.queue.Len() > dataPoints { // data type should always be uint32 firstItem = f.queue.Dequeue().(uint32) } // if (measurement - firstItem) < 0, uint64(measurement - firstItem) // will overflow and become a large positive number f.sum += uint64(measurement) f.sum -= uint64(firstItem) if measurement > f.max { f.max = measurement } if f.min == 0 || measurement < f.min { f.min = measurement } } // caller of ave() should acquire lock first func (f *flowControlData) ave() float64 { if f.queue.Len() == 0 { return 0 } return float64(f.sum) / float64(f.queue.Len()) } func (f *flowControlData) metrics() (ave float64, min, max uint32) { f.lock.RLock() defer f.lock.RUnlock() return f.ave(), f.min, f.max } func newRate() *rate { return &rate{} } func (r *rate) update(measurement uint64) { r.lock.Lock() defer r.lock.Unlock() r.curr = measurement // if measurement is 0, then there is no incoming/outgoing connection, don't update min/max if r.curr == 0 { return } if measurement > r.max { r.max = measurement } if r.min == 0 || measurement < r.min { r.min = measurement } } func (r *rate) get() (curr, min, max uint64) { r.lock.RLock() defer r.lock.RUnlock() return r.curr, r.min, r.max }