cpu: use wmic to get CPU usage on Windows.

cpu/cpu.go

@@ -5,7 +5,6 @@ import (
 	"runtime"
 	"strconv"
 	"strings"
-	"time"
 )
 
 type CPUTimesStat struct {
@@ -38,62 +37,11 @@ type CPUInfoStat struct {
 	Flags      []string `json:"flags"`
 }
 
-func CPUCounts(logical bool) (int, error) {
-	return runtime.NumCPU(), nil
-}
-
 var lastCPUTimes []CPUTimesStat
 var lastPerCPUTimes []CPUTimesStat
 
-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
-	}
-
-	cpuTimes, err := CPUTimes(percpu)
-	if err != nil {
-		return nil, err
-	}
-
-	if interval > 0 {
-		if !percpu {
-			lastCPUTimes = cpuTimes
-		} else {
-			lastPerCPUTimes = cpuTimes
-		}
-		time.Sleep(interval)
-		cpuTimes, err = CPUTimes(percpu)
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	ret := make([]float64, len(cpuTimes))
-	if !percpu {
-		ret[0] = calculate(lastCPUTimes[0], cpuTimes[0])
-		lastCPUTimes = cpuTimes
-	} else {
-		for i, t := range cpuTimes {
-			ret[i] = calculate(lastPerCPUTimes[i], t)
-		}
-		lastPerCPUTimes = cpuTimes
-	}
-	return ret, nil
+func CPUCounts(logical bool) (int, error) {
+	return runtime.NumCPU(), nil
 }
 
 func (c CPUTimesStat) String() string {

cpu/cpu_test.go

@@ -63,7 +63,10 @@ func TestCpuInfo(t *testing.T) {
 
 func testCPUPercent(t *testing.T, percpu bool) {
 	numcpu := runtime.NumCPU()
+	testCount := 3
+
 	if runtime.GOOS != "windows" {
+		testCount = 100
 		v, err := CPUPercent(time.Millisecond, percpu)
 		if err != nil {
 			t.Errorf("error %v", err)
@@ -72,7 +75,7 @@ func testCPUPercent(t *testing.T, percpu bool) {
 			t.Fatalf("wrong number of entries from CPUPercent: %v", v)
 		}
 	}
-	for i := 0; i < 100; i++ {
+	for i := 0; i < testCount; i++ {
 		duration := time.Duration(10) * time.Microsecond
 		v, err := CPUPercent(duration, percpu)
 		if err != nil {

cpu/cpu_unix.go

+// +build linux,freebsd,darwin
+
+package cpu
+
+import (
+	"encoding/json"
+	"strconv"
+	"strings"
+	"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
+	}
+
+	cpuTimes, err := CPUTimes(percpu)
+	if err != nil {
+		return nil, err
+	}
+
+	if interval > 0 {
+		if !percpu {
+			lastCPUTimes = cpuTimes
+		} else {
+			lastPerCPUTimes = cpuTimes
+		}
+		time.Sleep(interval)
+		cpuTimes, err = CPUTimes(percpu)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	ret := make([]float64, len(cpuTimes))
+	if !percpu {
+		ret[0] = calculate(lastCPUTimes[0], cpuTimes[0])
+		lastCPUTimes = cpuTimes
+	} else {
+		for i, t := range cpuTimes {
+			ret[i] = calculate(lastPerCPUTimes[i], t)
+		}
+		lastPerCPUTimes = cpuTimes
+	}
+	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)
+}

cpu/cpu_windows.go

@@ -6,6 +6,7 @@ import (
 	"strconv"
 	"strings"
 	"syscall"
+	"time"
 	"unsafe"
 
 	common "github.com/shirou/gopsutil/common"
@@ -79,3 +80,25 @@ func CPUInfo() ([]CPUInfoStat, error) {
 	}
 	return ret, nil
 }
+
+func CPUPercent(interval time.Duration, percpu bool) ([]float64, error) {
+	ret := []float64{}
+
+	lines, err := common.GetWmic("cpu", "loadpercentage")
+	if err != nil {
+		return ret, err
+	}
+	for _, l := range lines {
+		t := strings.Split(l, ",")
+
+		if len(t) < 2 {
+			continue
+		}
+		p, err := strconv.Atoi(t[1])
+		if err != nil {
+			p = 0
+		}
+		ret = append(ret, float64(p)/100.0)
+	}
+	return ret, nil
+}