open-nomad/vendor/github.com/shirou/gopsutil/cpu/cpu_unix.go
2016-06-17 13:24:10 -07:00

91 lines
2 KiB
Go

// +build linux freebsd darwin
package cpu
import (
"fmt"
"time"
)
func getAllBusy(t TimesStat) (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
}
func calculateBusy(t1, t2 TimesStat) 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
}
func calculateAllBusy(t1, t2 []TimesStat) ([]float64, error) {
// Make sure the CPU measurements have the same length.
if len(t1) != len(t2) {
return nil, fmt.Errorf(
"received two CPU counts: %d != %d",
len(t1), len(t2),
)
}
ret := make([]float64, len(t1))
for i, t := range t2 {
ret[i] = calculateBusy(t1[i], t)
}
return ret, nil
}
//Percent calculates the percentage of cpu used either per CPU or combined.
//If an interval of 0 is given it will compare the current cpu times against the last call.
func Percent(interval time.Duration, percpu bool) ([]float64, error) {
if interval <= 0 {
return percentUsedFromLastCall(percpu)
}
// Get CPU usage at the start of the interval.
cpuTimes1, err := Times(percpu)
if err != nil {
return nil, err
}
time.Sleep(interval)
// And at the end of the interval.
cpuTimes2, err := Times(percpu)
if err != nil {
return nil, err
}
return calculateAllBusy(cpuTimes1, cpuTimes2)
}
func percentUsedFromLastCall(percpu bool) ([]float64, error) {
cpuTimes, err := Times(percpu)
if err != nil {
return nil, err
}
lastCPUPercent.Lock()
defer lastCPUPercent.Unlock()
var lastTimes []TimesStat
if percpu {
lastTimes = lastCPUPercent.lastPerCPUTimes
lastCPUPercent.lastPerCPUTimes = cpuTimes
} else {
lastTimes = lastCPUPercent.lastCPUTimes
lastCPUPercent.lastCPUTimes = cpuTimes
}
if lastTimes == nil {
return nil, fmt.Errorf("Error getting times for cpu percent. LastTimes was nil")
}
return calculateAllBusy(lastTimes, cpuTimes)
}