// +build linux freebsd darwin package cpu import ( "fmt" "time" ) func CPUPercent(interval time.Duration, percpu bool) ([]float64, error) { getAllBusy := func(t CPUTimesStat) (float64, float64) { busy := t.User + t.System + t.Nice + t.Iowait + t.Irq + t.Softirq + t.Steal + t.Guest + t.GuestNice + t.Stolen return busy + t.Idle, busy } calculate := func(t1, t2 CPUTimesStat) float64 { t1All, t1Busy := getAllBusy(t1) t2All, t2Busy := getAllBusy(t2) if t2Busy <= t1Busy { return 0 } if t2All <= t1All { return 1 } return (t2Busy - t1Busy) / (t2All - t1All) * 100 } // Get CPU usage at the start of the interval. cpuTimes1, err := CPUTimes(percpu) if err != nil { return nil, err } if interval > 0 { time.Sleep(interval) } // And at the end of the interval. cpuTimes2, err := CPUTimes(percpu) if err != nil { return nil, err } // Make sure the CPU measurements have the same length. if len(cpuTimes1) != len(cpuTimes2) { return nil, fmt.Errorf( "received two CPU counts: %d != %d", len(cpuTimes1), len(cpuTimes2), ) } ret := make([]float64, len(cpuTimes1)) for i, t := range cpuTimes2 { ret[i] = calculate(cpuTimes1[i], t) } return ret, nil }