diff --git a/.example/net/gtrace/jaeger/main.go b/.example/net/gtrace/jaeger/main.go
new file mode 100644
index 000000000..87d32d26e
--- /dev/null
+++ b/.example/net/gtrace/jaeger/main.go
@@ -0,0 +1,79 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Command jaeger is an example program that creates spans
+// and uploads to Jaeger.
+package main
+
+import (
+	"context"
+	"fmt"
+	"github.com/gogf/gf/frame/g"
+	"go.opentelemetry.io/otel/exporters/trace/jaeger"
+	"go.opentelemetry.io/otel/trace"
+	"log"
+	"time"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/label"
+
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+)
+
+// initTracer creates a new trace provider instance and registers it as global trace provider.
+func initTracer() func() {
+	// Create and install Jaeger export pipeline.
+	flush, err := jaeger.InstallNewPipeline(
+		jaeger.WithCollectorEndpoint("http://localhost:14268/api/traces"),
+		jaeger.WithProcess(jaeger.Process{
+			ServiceName: "http-trace-demo",
+			Tags: []label.KeyValue{
+				label.String("exporter", "jaeger"),
+				label.Float64("float", 312.23),
+			},
+		}),
+		jaeger.WithSDK(&sdktrace.Config{DefaultSampler: sdktrace.AlwaysSample()}),
+	)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return flush
+}
+
+func main() {
+	ctx := context.Background()
+
+	flush := initTracer()
+	defer flush()
+
+	ctx, span := otel.Tracer("component-main").Start(ctx, "foo")
+	defer span.End()
+
+	content := g.Client().Ctx(ctx).Header(g.MapStrStr{
+		"test": "123",
+		"john": "smith",
+	}).Cookie(g.MapStrStr{
+		"cookieKey":"cookieValue",
+	}).GetContent("http://baidu.com/?q=goframe")
+	fmt.Println(content)
+}
+
+func bar(ctx context.Context) {
+	_, span := otel.Tracer("test").Start(ctx, "bar")
+	defer span.End()
+	span.AddEvent("Nice operation!", trace.WithAttributes(label.Int("bogons", 100)))
+	span.SetAttributes(label.String("test2", "123"))
+	time.Sleep(time.Second * 2)
+	// Do bar...
+}
diff --git a/go.mod b/go.mod
index 77c4f3f19..9b3716251 100644
--- a/go.mod
+++ b/go.mod
@@ -10,9 +10,16 @@ require (
 	github.com/gomodule/redigo v2.0.0+incompatible
 	github.com/gorilla/websocket v1.4.1
 	github.com/grokify/html-strip-tags-go v0.0.0-20190921062105-daaa06bf1aaf
+	github.com/kr/pretty v0.1.0 // indirect
 	github.com/mattn/go-runewidth v0.0.9 // indirect
 	github.com/olekukonko/tablewriter v0.0.1
-	golang.org/x/net v0.0.0-20200602114024-627f9648deb9
-	golang.org/x/text v0.3.2
+	go.opentelemetry.io/otel v0.16.0
+	go.opentelemetry.io/otel/exporters/trace/jaeger v0.16.0
+	go.opentelemetry.io/otel/sdk v0.16.0
+	golang.org/x/net v0.0.0-20201031054903-ff519b6c9102
+	golang.org/x/sys v0.0.0-20201201145000-ef89a241ccb3 // indirect
+	golang.org/x/text v0.3.4
+	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
+	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c
 )
diff --git a/net/ghttp/ghttp_client_config.go b/net/ghttp/ghttp_client.go
similarity index 94%
rename from net/ghttp/ghttp_client_config.go
rename to net/ghttp/ghttp_client.go
index b90d57665..089efc7c9 100644
--- a/net/ghttp/ghttp_client_config.go
+++ b/net/ghttp/ghttp_client.go
@@ -9,6 +9,8 @@ package ghttp
 import (
 	"context"
 	"crypto/tls"
+	"fmt"
+	"github.com/gogf/gf"
 	"github.com/gogf/gf/text/gstr"
 	"golang.org/x/net/proxy"
 	"net"
@@ -24,6 +26,7 @@ import (
 type Client struct {
 	http.Client                           // Underlying HTTP Client.
 	ctx               context.Context     // Context for each request.
+	agent             string              // Client agent.
 	parent            *Client             // Parent http client, this is used for chaining operations.
 	header            map[string]string   // Custom header map.
 	cookies           map[string]string   // Custom cookie map.
@@ -36,6 +39,10 @@ type Client struct {
 	middlewareHandler []ClientHandlerFunc // Interceptor handlers
 }
 
+var (
+	defaultClientAgent = fmt.Sprintf(`GoFrameHTTPClient %s`, gf.VERSION)
+)
+
 // NewClient creates and returns a new HTTP client object.
 func NewClient() *Client {
 	return &Client{
@@ -50,6 +57,7 @@ func NewClient() *Client {
 		},
 		header:  make(map[string]string),
 		cookies: make(map[string]string),
+		agent:   defaultClientAgent,
 	}
 }
 
@@ -90,6 +98,12 @@ func (c *Client) SetHeaderMap(m map[string]string) *Client {
 	return c
 }
 
+// SetAgent sets the User-Agent header for client.
+func (c *Client) SetAgent(agent string) *Client {
+	c.header["User-Agent"] = agent
+	return c
+}
+
 // SetContentType sets HTTP content type for the client.
 func (c *Client) SetContentType(contentType string) *Client {
 	c.header["Content-Type"] = contentType
diff --git a/net/ghttp/ghttp_client_request.go b/net/ghttp/ghttp_client_request.go
index f407c59e6..3d3775922 100644
--- a/net/ghttp/ghttp_client_request.go
+++ b/net/ghttp/ghttp_client_request.go
@@ -11,9 +11,13 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"github.com/gogf/gf"
 	"github.com/gogf/gf/internal/intlog"
 	"github.com/gogf/gf/internal/json"
 	"github.com/gogf/gf/internal/utils"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/label"
+	"go.opentelemetry.io/otel/trace"
 	"io"
 	"io/ioutil"
 	"mime/multipart"
@@ -97,6 +101,19 @@ func (c *Client) DoRequest(method, url string, data ...interface{}) (resp *Clien
 		return nil, err
 	}
 
+	// Tracing.
+	tr := otel.GetTracerProvider().Tracer(
+		"github.com/gogf/gf/net/ghttp.client",
+		trace.WithInstrumentationVersion(fmt.Sprintf(`%s`, gf.VERSION)),
+	)
+	ctx, span := tr.Start(req.Context(), req.URL.String())
+	defer span.End()
+	// Header (Cookie is in it).
+	if len(req.Header) > 0 {
+		span.SetAttributes(label.Any(`http.headers`, req.Header))
+	}
+	req = req.WithContext(ctx)
+
 	// Client middleware.
 	if len(c.middlewareHandler) > 0 {
 		mdlHandlers := make([]ClientHandlerFunc, 0, len(c.middlewareHandler)+1)
@@ -278,6 +295,10 @@ func (c *Client) prepareRequest(method, url string, data ...interface{}) (req *h
 	if len(c.authUser) > 0 {
 		req.SetBasicAuth(c.authUser, c.authPass)
 	}
+	// Client agent.
+	if c.agent != "" {
+		req.Header.Set("User-Agent", c.agent)
+	}
 	return req, nil
 }
 
diff --git a/net/gtrace/gtrace_http_client.go b/net/gtrace/gtrace_http_client.go
new file mode 100644
index 000000000..7bc100b22
--- /dev/null
+++ b/net/gtrace/gtrace_http_client.go
@@ -0,0 +1,242 @@
+package gtrace
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"github.com/gogf/gf"
+	"net/http/httptrace"
+	"net/textproto"
+	"strings"
+	"sync"
+
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/codes"
+	"go.opentelemetry.io/otel/label"
+	"go.opentelemetry.io/otel/semconv"
+	"go.opentelemetry.io/otel/trace"
+)
+
+var (
+	HTTPStatus     = label.Key("http.status")
+	HTTPHeaderMIME = label.Key("http.mime")
+	HTTPRemoteAddr = label.Key("http.remote")
+	HTTPLocalAddr  = label.Key("http.local")
+)
+
+var (
+	hookMap = map[string]string{
+		"http.dns":     "http.getconn",
+		"http.connect": "http.getconn",
+		"http.tls":     "http.getconn",
+	}
+)
+
+func parentHook(hook string) string {
+	if strings.HasPrefix(hook, "http.connect") {
+		return hookMap["http.connect"]
+	}
+	return hookMap[hook]
+}
+
+type clientTracer struct {
+	context.Context
+
+	tr trace.Tracer
+
+	activeHooks map[string]context.Context
+	root        trace.Span
+	mtx         sync.Mutex
+}
+
+func NewClientTrace(ctx context.Context) *httptrace.ClientTrace {
+	ct := &clientTracer{
+		Context:     ctx,
+		activeHooks: make(map[string]context.Context),
+	}
+
+	ct.tr = otel.GetTracerProvider().Tracer(
+		"github.com/gogf/gf/net/ghttp.client",
+		trace.WithInstrumentationVersion(fmt.Sprintf(`%s`, gf.VERSION)),
+	)
+
+	return &httptrace.ClientTrace{
+		GetConn:              ct.getConn,
+		GotConn:              ct.gotConn,
+		PutIdleConn:          ct.putIdleConn,
+		GotFirstResponseByte: ct.gotFirstResponseByte,
+		Got100Continue:       ct.got100Continue,
+		Got1xxResponse:       ct.got1xxResponse,
+		DNSStart:             ct.dnsStart,
+		DNSDone:              ct.dnsDone,
+		ConnectStart:         ct.connectStart,
+		ConnectDone:          ct.connectDone,
+		TLSHandshakeStart:    ct.tlsHandshakeStart,
+		TLSHandshakeDone:     ct.tlsHandshakeDone,
+		WroteHeaderField:     ct.wroteHeaderField,
+		WroteHeaders:         ct.wroteHeaders,
+		Wait100Continue:      ct.wait100Continue,
+		WroteRequest:         ct.wroteRequest,
+	}
+}
+
+func (ct *clientTracer) start(hook, spanName string, attrs ...label.KeyValue) {
+	ct.mtx.Lock()
+	defer ct.mtx.Unlock()
+
+	if hookCtx, found := ct.activeHooks[hook]; !found {
+		var sp trace.Span
+		ct.activeHooks[hook], sp = ct.tr.Start(ct.getParentContext(hook), spanName, trace.WithAttributes(attrs...), trace.WithSpanKind(trace.SpanKindClient))
+		if ct.root == nil {
+			ct.root = sp
+		}
+	} else {
+		// end was called before start finished, add the start attributes and end the span here
+		span := trace.SpanFromContext(hookCtx)
+		span.SetAttributes(attrs...)
+		span.End()
+
+		delete(ct.activeHooks, hook)
+	}
+}
+
+func (ct *clientTracer) end(hook string, err error, attrs ...label.KeyValue) {
+	ct.mtx.Lock()
+	defer ct.mtx.Unlock()
+	if ctx, ok := ct.activeHooks[hook]; ok {
+		span := trace.SpanFromContext(ctx)
+		if err != nil {
+			span.SetStatus(codes.Error, err.Error())
+		}
+		span.SetAttributes(attrs...)
+		span.End()
+		delete(ct.activeHooks, hook)
+	} else {
+		// start is not finished before end is called.
+		// Start a span here with the ending attributes that will be finished when start finishes.
+		// Yes, it's backwards. v0v
+		ctx, span := ct.tr.Start(ct.getParentContext(hook), hook, trace.WithAttributes(attrs...), trace.WithSpanKind(trace.SpanKindClient))
+		if err != nil {
+			span.SetStatus(codes.Error, err.Error())
+		}
+		ct.activeHooks[hook] = ctx
+	}
+}
+
+func (ct *clientTracer) getParentContext(hook string) context.Context {
+	ctx, ok := ct.activeHooks[parentHook(hook)]
+	if !ok {
+		return ct.Context
+	}
+	return ctx
+}
+
+func (ct *clientTracer) span(hook string) trace.Span {
+	ct.mtx.Lock()
+	defer ct.mtx.Unlock()
+	if ctx, ok := ct.activeHooks[hook]; ok {
+		return trace.SpanFromContext(ctx)
+	}
+	return nil
+}
+
+func (ct *clientTracer) getConn(host string) {
+	ct.start("http.getconn", "http.getconn", semconv.HTTPHostKey.String(host))
+}
+
+func (ct *clientTracer) gotConn(info httptrace.GotConnInfo) {
+	ct.end("http.getconn",
+		nil,
+		HTTPRemoteAddr.String(info.Conn.RemoteAddr().String()),
+		HTTPLocalAddr.String(info.Conn.LocalAddr().String()),
+	)
+}
+
+func (ct *clientTracer) putIdleConn(err error) {
+	ct.end("http.receive", err)
+}
+
+func (ct *clientTracer) gotFirstResponseByte() {
+	ct.start("http.receive", "http.receive")
+}
+
+func (ct *clientTracer) dnsStart(info httptrace.DNSStartInfo) {
+	ct.start("http.dns", "http.dns", semconv.HTTPHostKey.String(info.Host))
+}
+
+func (ct *clientTracer) dnsDone(info httptrace.DNSDoneInfo) {
+	ct.end("http.dns", info.Err)
+}
+
+func (ct *clientTracer) connectStart(network, addr string) {
+	ct.start("http.connect."+addr, "http.connect", HTTPRemoteAddr.String(addr))
+}
+
+func (ct *clientTracer) connectDone(network, addr string, err error) {
+	ct.end("http.connect."+addr, err)
+}
+
+func (ct *clientTracer) tlsHandshakeStart() {
+	ct.start("http.tls", "http.tls")
+}
+
+func (ct *clientTracer) tlsHandshakeDone(_ tls.ConnectionState, err error) {
+	ct.end("http.tls", err)
+}
+
+func (ct *clientTracer) wroteHeaderField(k string, v []string) {
+	if ct.span("http.headers") == nil {
+		ct.start("http.headers", "http.headers")
+	}
+	ct.root.SetAttributes(label.String("http."+strings.ToLower(k), sliceToString(v)))
+}
+
+func (ct *clientTracer) wroteHeaders() {
+	if ct.span("http.headers") != nil {
+		ct.end("http.headers", nil)
+	}
+	ct.start("http.send", "http.send")
+}
+
+func (ct *clientTracer) wroteRequest(info httptrace.WroteRequestInfo) {
+	if info.Err != nil {
+		ct.root.SetStatus(codes.Error, info.Err.Error())
+	}
+	ct.end("http.send", info.Err)
+}
+
+func (ct *clientTracer) got100Continue() {
+	ct.span("http.receive").AddEvent("GOT 100 - Continue")
+}
+
+func (ct *clientTracer) wait100Continue() {
+	ct.span("http.receive").AddEvent("GOT 100 - Wait")
+}
+
+func (ct *clientTracer) got1xxResponse(code int, header textproto.MIMEHeader) error {
+	ct.span("http.receive").AddEvent("GOT 1xx", trace.WithAttributes(
+		HTTPStatus.Int(code),
+		HTTPHeaderMIME.String(sm2s(header)),
+	))
+	return nil
+}
+
+func sliceToString(value []string) string {
+	if len(value) == 0 {
+		return "undefined"
+	}
+	return strings.Join(value, ",")
+}
+
+func sm2s(value map[string][]string) string {
+	var buf strings.Builder
+	for k, v := range value {
+		if buf.Len() != 0 {
+			buf.WriteString(",")
+		}
+		buf.WriteString(k)
+		buf.WriteString("=")
+		buf.WriteString(sliceToString(v))
+	}
+	return buf.String()
+}
diff --git a/os/gcron/gcron_unit_1_test.go b/os/gcron/gcron_unit_1_test.go
index 5cb253c11..0807f4f4f 100644
--- a/os/gcron/gcron_unit_1_test.go
+++ b/os/gcron/gcron_unit_1_test.go
@@ -7,6 +7,7 @@
 package gcron_test
 
 import (
+	"github.com/gogf/gf/os/glog"
 	"testing"
 	"time"
 
@@ -20,18 +21,19 @@ func TestCron_Add_Close(t *testing.T) {
 		cron := gcron.New()
 		array := garray.New(true)
 		_, err1 := cron.Add("* * * * * *", func() {
-			//glog.Println("cron1")
+			glog.Println("cron1")
 			array.Append(1)
 		})
 		_, err2 := cron.Add("* * * * * *", func() {
-			//glog.Println("cron2")
+			glog.Println("cron2")
 			array.Append(1)
 		}, "test")
 		_, err3 := cron.Add("* * * * * *", func() {
+			glog.Println("cron3")
 			array.Append(1)
 		}, "test")
 		_, err4 := cron.Add("@every 2s", func() {
-			//glog.Println("cron3")
+			glog.Println("cron4")
 			array.Append(1)
 		})
 		t.Assert(err1, nil)
@@ -39,7 +41,7 @@ func TestCron_Add_Close(t *testing.T) {
 		t.AssertNE(err3, nil)
 		t.Assert(err4, nil)
 		t.Assert(cron.Size(), 3)
-		time.Sleep(1200 * time.Millisecond)
+		time.Sleep(1300 * time.Millisecond)
 		t.Assert(array.Len(), 2)
 		time.Sleep(1400 * time.Millisecond)
 		t.Assert(array.Len(), 5)
diff --git a/os/gcron/gcron_unit_2_test.go b/os/gcron/gcron_unit_2_test.go
index f3c8935e2..fc157a929 100644
--- a/os/gcron/gcron_unit_2_test.go
+++ b/os/gcron/gcron_unit_2_test.go
@@ -47,7 +47,7 @@ func TestCron_Entry_Operations(t *testing.T) {
 		t.Assert(array.Len(), 1)
 		t.Assert(cron.Size(), 1)
 		entry.Stop()
-		time.Sleep(2000 * time.Millisecond)
+		time.Sleep(5000 * time.Millisecond)
 		t.Assert(array.Len(), 1)
 		t.Assert(cron.Size(), 1)
 		entry.Start()