support cgroup for limit resource

README.md

@@ -91,6 +91,24 @@ see complete example at: [opencv](./examples/opencv.go)
 
 result: ![image](./examples/sample_data/face-detect.jpg)
 
+## Set cpu limit/request for ffmpeg-go
+
+```go
+e := ComplexFilterExample("./sample_data/in1.mp4", "./sample_data/overlay.png", "./sample_data/out2.mp4")
+err := e.RunWithResource(0.1, 0.5)
+if err != nil {
+    assert.Nil(t, err)
+}
+```
+
+result from command top: we will see ffmpeg used 0.5 core as expected.
+
+```bash
+> top 
+PID    USER       PR  NI    VIRT    RES    SHR S  %CPU   %MEM     TIME+ COMMAND
+1386105 root      20   0 2114152 273780  31672 R  50.2   1.7      0:16.79 ffmpeg
+```
+
 # View Graph
 
 function view generate [mermaid](https://mermaid-js.github.io/mermaid/#/) chart, which can be use in markdown or view [online](https://mermaid-js.github.io/mermaid-live-editor/)

examples/limitcpu_test.go

@@ -0,0 +1,33 @@
+//+build linux
+
+package examples
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	ffmpeg "github.com/u2takey/ffmpeg-go"
+)
+
+func ComplexFilterExample(testInputFile, testOverlayFile, testOutputFile string) *ffmpeg.Stream {
+	split := ffmpeg.Input(testInputFile).VFlip().Split()
+	split0, split1 := split.Get("0"), split.Get("1")
+	overlayFile := ffmpeg.Input(testOverlayFile).Crop(10, 10, 158, 112)
+	return ffmpeg.Concat([]*ffmpeg.Stream{
+		split0.Trim(ffmpeg.KwArgs{"start_frame": 10, "end_frame": 20}),
+		split1.Trim(ffmpeg.KwArgs{"start_frame": 30, "end_frame": 40})}).
+		Overlay(overlayFile.HFlip(), "").
+		DrawBox(50, 50, 120, 120, "red", 5).
+		Output(testOutputFile).
+		OverWriteOutput()
+}
+
+// PID    USER       PR  NI    VIRT    RES    SHR S  %CPU   %MEM     TIME+ COMMAND
+// 1386105 root      20   0 2114152 273780  31672 R  50.2   1.7      0:16.79 ffmpeg
+func TestLimitCpu(t *testing.T) {
+	e := ComplexFilterExample("./sample_data/in1.mp4", "./sample_data/overlay.png", "./sample_data/out2.mp4")
+	err := e.WithCpuCoreRequest(0.1).WithCpuCoreLimit(0.5).RunLinux()
+	if err != nil {
+		assert.Nil(t, err)
+	}
+}

examples/opencv.go

@@ -81,6 +81,8 @@ func openCvProcess(xmlFile string, reader io.ReadCloser, w, h int) {
 
 		// show the image in the window, and wait 1 millisecond
 		window.IMShow(img2)
+		img.Close()
+		img2.Close()
 		if window.WaitKey(10) >= 0 {
 			break
 		}

run_linux.go

@@ -0,0 +1,138 @@
+package ffmpeg_go
+
+import (
+	"context"
+	"errors"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strconv"
+
+	"github.com/u2takey/go-utils/rand"
+)
+
+const (
+	cgroupConfigKey = "cgroupConfig"
+	cpuRoot         = "/sys/fs/cgroup/cpu,cpuacct"
+	cpuSetRoot      = "/sys/fs/cgroup/cpuset"
+	procsFile       = "cgroup.procs"
+	cpuSharesFile   = "cpu.shares"
+	cfsPeriodUsFile = "cpu.cfs_period_us"
+	cfsQuotaUsFile  = "cpu.cfs_quota_us"
+	cpuSetCpusFile  = "cpuset.cpus"
+	cpuSetMemsFile  = "cpuset.mems"
+)
+
+type cgroupConfig struct {
+	cpuRequest float32
+	cpuLimit   float32
+	cpuset     string
+	memset     string
+}
+
+func (s *Stream) setCGroupConfig(f func(config *cgroupConfig)) *Stream {
+	a := s.Context.Value(cgroupConfigKey)
+	if a == nil {
+		a = &cgroupConfig{}
+	}
+	f(a.(*cgroupConfig))
+	s.Context = context.WithValue(s.Context, cgroupConfigKey, a)
+	return s
+}
+
+func (s *Stream) WithCpuCoreRequest(n float32) *Stream {
+	return s.setCGroupConfig(func(config *cgroupConfig) {
+		config.cpuRequest = n
+	})
+}
+
+func (s *Stream) WithCpuCoreLimit(n float32) *Stream {
+	return s.setCGroupConfig(func(config *cgroupConfig) {
+		config.cpuLimit = n
+	})
+}
+
+func (s *Stream) WithCpuSet(n string) *Stream {
+	return s.setCGroupConfig(func(config *cgroupConfig) {
+		config.cpuset = n
+	})
+}
+
+func (s *Stream) WithMemSet(n string) *Stream {
+	return s.setCGroupConfig(func(config *cgroupConfig) {
+		config.memset = n
+	})
+}
+
+func writeCGroupFile(rootPath, file string, value string) error {
+	return ioutil.WriteFile(filepath.Join(rootPath, file), []byte(value), 0755)
+}
+
+func (s *Stream) RunLinux() error {
+	a := s.Context.Value(cgroupConfigKey).(*cgroupConfig)
+	if a.cpuRequest > a.cpuLimit {
+		return errors.New("cpuCoreLimit should greater or equal to cpuCoreRequest")
+	}
+	name := "ffmpeg_go_" + rand.String(6)
+	rootCpuPath, rootCpuSetPath := filepath.Join(cpuRoot, name), filepath.Join(cpuSetRoot, name)
+	err := os.MkdirAll(rootCpuPath, 0777)
+	if err != nil {
+		return err
+	}
+	err = os.MkdirAll(rootCpuSetPath, 0777)
+	if err != nil {
+		return err
+	}
+	defer func() { _ = os.Remove(rootCpuPath); _ = os.Remove(rootCpuSetPath) }()
+
+	share := int(1024 * a.cpuRequest)
+	period := 100000
+	quota := int(a.cpuLimit * 100000)
+
+	if share > 0 {
+		err = writeCGroupFile(rootCpuPath, cpuSharesFile, strconv.Itoa(share))
+		if err != nil {
+			return err
+		}
+	}
+	err = writeCGroupFile(rootCpuPath, cfsPeriodUsFile, strconv.Itoa(period))
+	if err != nil {
+		return err
+	}
+	if quota > 0 {
+		err = writeCGroupFile(rootCpuPath, cfsQuotaUsFile, strconv.Itoa(quota))
+		if err != nil {
+			return err
+		}
+	}
+	if a.cpuset != "" && a.memset != "" {
+		err = writeCGroupFile(rootCpuSetPath, cpuSetCpusFile, a.cpuset)
+		if err != nil {
+			return err
+		}
+		err = writeCGroupFile(rootCpuSetPath, cpuSetMemsFile, a.memset)
+		if err != nil {
+			return err
+		}
+	}
+
+	cmd := s.Compile()
+	err = cmd.Start()
+	if err != nil {
+		return err
+	}
+	if share > 0 || quota > 0 {
+		err = writeCGroupFile(rootCpuPath, procsFile, strconv.Itoa(cmd.Process.Pid))
+		if err != nil {
+			return err
+		}
+	}
+	if a.cpuset != "" && a.memset != "" {
+		err = writeCGroupFile(rootCpuSetPath, procsFile, strconv.Itoa(cmd.Process.Pid))
+		if err != nil {
+			return err
+		}
+	}
+
+	return cmd.Wait()
+}