moleculer-go/moleculer

package util

import (
    "time"

    "github.com/shirou/gopsutil/cpu"
)

func GetCpuUsage(sampleTime time.Duration) (float64, error) {
    first, err := cpu.Times(false)
    if err != nil {
        return 0, err
    }

    time.Sleep(sampleTime)

    second, err := cpu.Times(false)
    if err != nil {
        return 0, err
    }

    time.Sleep(sampleTime)

    third, err := cpu.Times(false)
    if err != nil {
        return 0, err
    }

    var totalPerc float64
    for i, _ := range first {
        firstUsage := calcUsage(first[i], second[i])
        secondUsage := calcUsage(second[i], third[i])
        totalPerc += (firstUsage + secondUsage) / 2
    }

    avg := totalPerc / float64(len(first))
    return avg, nil
}

func calcUsage(first cpu.TimesStat, second cpu.TimesStat) float64 {
    firstTotal := getTotalTime(first)
    secondTotal := getTotalTime(second)
    total := secondTotal - firstTotal
    idle := second.Idle - first.Idle
    return (total - idle) / total
}

func getTotalTime(t cpu.TimesStat) float64 {
    return t.User + t.System + t.Idle + t.Nice + t.Iowait + t.Irq + t.Softirq + t.Steal
}