VictoriaMetrics/vendor/github.com/cheggaaa/pb/v3/speed.go
Aliaksandr Valialkin d5c180e680 app/vmctl: move vmctl code from github.com/VictoriaMetrics/vmctl
It is better developing vmctl tool in VictoriaMetrics repository, so it could be released
together with the rest of vmutils tools such as vmalert, vmagent, vmbackup, vmrestore and vmauth.
2021-02-01 01:10:20 +02:00

83 lines
2 KiB
Go

package pb
import (
"fmt"
"math"
"time"
"github.com/VividCortex/ewma"
)
var speedAddLimit = time.Second / 2
type speed struct {
ewma ewma.MovingAverage
lastStateId uint64
prevValue, startValue int64
prevTime, startTime time.Time
}
func (s *speed) value(state *State) float64 {
if s.ewma == nil {
s.ewma = ewma.NewMovingAverage()
}
if state.IsFirst() || state.Id() < s.lastStateId {
s.reset(state)
return 0
}
if state.Id() == s.lastStateId {
return s.ewma.Value()
}
if state.IsFinished() {
return s.absValue(state)
}
dur := state.Time().Sub(s.prevTime)
if dur < speedAddLimit {
return s.ewma.Value()
}
diff := math.Abs(float64(state.Value() - s.prevValue))
lastSpeed := diff / dur.Seconds()
s.prevTime = state.Time()
s.prevValue = state.Value()
s.lastStateId = state.Id()
s.ewma.Add(lastSpeed)
return s.ewma.Value()
}
func (s *speed) reset(state *State) {
s.lastStateId = state.Id()
s.startTime = state.Time()
s.prevTime = state.Time()
s.startValue = state.Value()
s.prevValue = state.Value()
s.ewma = ewma.NewMovingAverage()
}
func (s *speed) absValue(state *State) float64 {
if dur := state.Time().Sub(s.startTime); dur > 0 {
return float64(state.Value()) / dur.Seconds()
}
return 0
}
func getSpeedObj(state *State) (s *speed) {
if sObj, ok := state.Get(speedObj).(*speed); ok {
return sObj
}
s = new(speed)
state.Set(speedObj, s)
return
}
// ElementSpeed calculates current speed by EWMA
// Optionally can take one or two string arguments.
// First string will be used as value for format speed, default is "%s p/s".
// Second string will be used when speed not available, default is "? p/s"
// In template use as follows: {{speed .}} or {{speed . "%s per second"}} or {{speed . "%s ps" "..."}
var ElementSpeed ElementFunc = func(state *State, args ...string) string {
sp := getSpeedObj(state).value(state)
if sp == 0 {
return argsHelper(args).getNotEmptyOr(1, "? p/s")
}
return fmt.Sprintf(argsHelper(args).getNotEmptyOr(0, "%s p/s"), state.Format(int64(round(sp))))
}