fix(cpu): fix cpu total and busy calc

cpu/cpu.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"math"
+	"runtime"
 	"strconv"
 	"strings"
 	"sync"
@@ -86,10 +87,12 @@ func (c TimesStat) String() string {
 	return `{` + strings.Join(v, ",") + `}`
 }
 
-// Total returns the total number of seconds in a CPUTimesStat
+// Deprecated: Total returns the total number of seconds in a CPUTimesStat
+// Please do not use this internal function.
 func (c TimesStat) Total() float64 {
-	total := c.User + c.System + c.Nice + c.Iowait + c.Irq + c.Softirq +
+	total := c.User + c.System + c.Idle + c.Nice + c.Iowait + c.Irq +
-		c.Steal + c.Idle
+		c.Softirq + c.Steal + c.Guest + c.GuestNice
+
 	return total
 }
 
@@ -99,9 +102,15 @@ func (c InfoStat) String() string {
 }
 
 func getAllBusy(t TimesStat) (float64, float64) {
-	busy := t.User + t.System + t.Nice + t.Iowait + t.Irq +
+	tot := t.Total()
-		t.Softirq + t.Steal
+	if runtime.GOOS == "linux" {
-	return busy + t.Idle, busy
+		tot -= t.Guest     // Linux 2.6.24+
+		tot -= t.GuestNice // Linux 3.2.0+
+	}
+
+	busy := tot - t.Idle - t.Iowait
+
+	return tot, busy
 }
 
 func calculateBusy(t1, t2 TimesStat) float64 {