diff --git a/cpu/cpu_unix.go b/cpu/cpu_unix.go
index 4871fcd..fd488a2 100644
--- a/cpu/cpu_unix.go
+++ b/cpu/cpu_unix.go
@@ -1,13 +1,13 @@
-// +build linux,freebsd,darwin
+// +build linux freebsd darwin
 
 package cpu
 
-import (
-	"encoding/json"
-	"strconv"
-	"strings"
-	"time"
-)
+import "time"
+
+func init() {
+	lastCPUTimes, _ = CPUTimes(false)
+	lastPerCPUTimes, _ = CPUTimes(true)
+}
 
 func CPUPercent(interval time.Duration, percpu bool) ([]float64, error) {
 	getAllBusy := func(t CPUTimesStat) (float64, float64) {
@@ -59,32 +59,3 @@ func CPUPercent(interval time.Duration, percpu bool) ([]float64, error) {
 	}
 	return ret, nil
 }
-
-func (c CPUTimesStat) String() string {
-	v := []string{
-		`"cpu":"` + c.CPU + `"`,
-		`"user":` + strconv.FormatFloat(c.User, 'f', 1, 64),
-		`"system":` + strconv.FormatFloat(c.System, 'f', 1, 64),
-		`"idle":` + strconv.FormatFloat(c.Idle, 'f', 1, 64),
-		`"nice":` + strconv.FormatFloat(c.Nice, 'f', 1, 64),
-		`"iowait":` + strconv.FormatFloat(c.Iowait, 'f', 1, 64),
-		`"irq":` + strconv.FormatFloat(c.Irq, 'f', 1, 64),
-		`"softirq":` + strconv.FormatFloat(c.Softirq, 'f', 1, 64),
-		`"steal":` + strconv.FormatFloat(c.Steal, 'f', 1, 64),
-		`"guest":` + strconv.FormatFloat(c.Guest, 'f', 1, 64),
-		`"guest_nice":` + strconv.FormatFloat(c.GuestNice, 'f', 1, 64),
-		`"stolen":` + strconv.FormatFloat(c.Stolen, 'f', 1, 64),
-	}
-
-	return `{` + strings.Join(v, ",") + `}`
-}
-
-func (c CPUInfoStat) String() string {
-	s, _ := json.Marshal(c)
-	return string(s)
-}
-
-func init() {
-	lastCPUTimes, _ = CPUTimes(false)
-	lastPerCPUTimes, _ = CPUTimes(true)
-}
diff --git a/cpu/cpu_windows.go b/cpu/cpu_windows.go
index 0980aa0..a19e4ce 100644
--- a/cpu/cpu_windows.go
+++ b/cpu/cpu_windows.go
@@ -98,6 +98,7 @@ func CPUPercent(interval time.Duration, percpu bool) ([]float64, error) {
 		if err != nil {
 			p = 0
 		}
+		// but windows can only get one percent.
 		ret = append(ret, float64(p)/100.0)
 	}
 	return ret, nil