diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0a3068ed..9bf94fd1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,5 @@
 # developing
+- Remove `duration` from prometheus labels. [4391](https://github.com/beego/beego/pull/4391)
 - Fix `unknown escape sequence` in generated code. [4385](https://github.com/beego/beego/pull/4385)
 - Using fixed name `commentRouter.go` as generated file name. [4385](https://github.com/beego/beego/pull/4385)
 - Fix 4383: ORM Adapter produces panic when using orm.RegisterModelWithPrefix. [4386](https://github.com/beego/beego/pull/4386)
\ No newline at end of file
diff --git a/adapter/metric/prometheus.go b/adapter/metric/prometheus.go
index 7abd0e5a..6b276171 100644
--- a/adapter/metric/prometheus.go
+++ b/adapter/metric/prometheus.go
@@ -38,7 +38,7 @@ func PrometheusMiddleWare(next http.Handler) http.Handler {
 			"appname": web.BConfig.AppName,
 		},
 		Help: "The statics info for http request",
-	}, []string{"pattern", "method", "status", "duration"})
+	}, []string{"pattern", "method", "status"})
 
 	prometheus.MustRegister(summaryVec)
 
@@ -96,5 +96,5 @@ func report(dur time.Duration, writer http.ResponseWriter, q *http.Request, vec
 		logs.Warn("we can not find the router info for this request, so request will be recorded as UNKNOWN: " + q.URL.String())
 	}
 	ms := dur / time.Millisecond
-	vec.WithLabelValues(ptn, q.Method, strconv.Itoa(status), strconv.Itoa(int(ms))).Observe(float64(ms))
+	vec.WithLabelValues(ptn, q.Method, strconv.Itoa(status)).Observe(float64(ms))
 }
diff --git a/adapter/metric/prometheus_test.go b/adapter/metric/prometheus_test.go
index e87e06d6..53984845 100644
--- a/adapter/metric/prometheus_test.go
+++ b/adapter/metric/prometheus_test.go
@@ -35,7 +35,7 @@ func TestPrometheusMiddleWare(t *testing.T) {
 		},
 		Method: "POST",
 	}
-	vec := prometheus.NewSummaryVec(prometheus.SummaryOpts{}, []string{"pattern", "method", "status", "duration"})
+	vec := prometheus.NewSummaryVec(prometheus.SummaryOpts{}, []string{"pattern", "method", "status"})
 
 	report(time.Second, writer, request, vec)
 	middleware.ServeHTTP(writer, request)
diff --git a/client/httplib/filter/prometheus/filter.go b/client/httplib/filter/prometheus/filter.go
index a4de521b..3d5acf12 100644
--- a/client/httplib/filter/prometheus/filter.go
+++ b/client/httplib/filter/prometheus/filter.go
@@ -43,7 +43,7 @@ func (builder *FilterChainBuilder) FilterChain(next httplib.Filter) httplib.Filt
 			"appname": builder.AppName,
 		},
 		Help: "The statics info for remote http requests",
-	}, []string{"proto", "scheme", "method", "host", "path", "status", "duration", "isError"})
+	}, []string{"proto", "scheme", "method", "host", "path", "status", "isError"})
 
 	return func(ctx context.Context, req *httplib.BeegoHTTPRequest) (*http.Response, error) {
 		startTime := time.Now()
@@ -73,5 +73,5 @@ func (builder *FilterChainBuilder) report(startTime time.Time, endTime time.Time
 	dur := int(endTime.Sub(startTime) / time.Millisecond)
 
 	builder.summaryVec.WithLabelValues(proto, scheme, method, host, path,
-		strconv.Itoa(status), strconv.Itoa(dur), strconv.FormatBool(err == nil))
+		strconv.Itoa(status), strconv.FormatBool(err != nil)).Observe(float64(dur))
 }
diff --git a/client/orm/filter/prometheus/filter.go b/client/orm/filter/prometheus/filter.go
index 1f30f770..db60876e 100644
--- a/client/orm/filter/prometheus/filter.go
+++ b/client/orm/filter/prometheus/filter.go
@@ -50,7 +50,7 @@ func (builder *FilterChainBuilder) FilterChain(next orm.Filter) orm.Filter {
 			"appname": builder.AppName,
 		},
 		Help: "The statics info for orm operation",
-	}, []string{"method", "name", "duration", "insideTx", "txName"})
+	}, []string{"method", "name", "insideTx", "txName"})
 
 	return func(ctx context.Context, inv *orm.Invocation) []interface{} {
 		startTime := time.Now()
@@ -74,12 +74,12 @@ func (builder *FilterChainBuilder) report(ctx context.Context, inv *orm.Invocati
 		builder.reportTxn(ctx, inv)
 		return
 	}
-	builder.summaryVec.WithLabelValues(inv.Method, inv.GetTableName(), strconv.Itoa(int(dur)),
-		strconv.FormatBool(inv.InsideTx), inv.TxName)
+	builder.summaryVec.WithLabelValues(inv.Method, inv.GetTableName(),
+		strconv.FormatBool(inv.InsideTx), inv.TxName).Observe(float64(dur))
 }
 
 func (builder *FilterChainBuilder) reportTxn(ctx context.Context, inv *orm.Invocation) {
 	dur := time.Now().Sub(inv.TxStartTime) / time.Millisecond
-	builder.summaryVec.WithLabelValues(inv.Method, inv.TxName, strconv.Itoa(int(dur)),
-		strconv.FormatBool(inv.InsideTx), inv.TxName)
+	builder.summaryVec.WithLabelValues(inv.Method, inv.TxName,
+		strconv.FormatBool(inv.InsideTx), inv.TxName).Observe(float64(dur))
 }
diff --git a/server/web/filter/prometheus/filter.go b/server/web/filter/prometheus/filter.go
index 5a0db9a7..59a673ac 100644
--- a/server/web/filter/prometheus/filter.go
+++ b/server/web/filter/prometheus/filter.go
@@ -43,7 +43,7 @@ func (builder *FilterChainBuilder) FilterChain(next web.FilterFunc) web.FilterFu
 			"appname": web.BConfig.AppName,
 		},
 		Help: "The statics info for http request",
-	}, []string{"pattern", "method", "status", "duration"})
+	}, []string{"pattern", "method", "status"})
 
 	prometheus.MustRegister(summaryVec)
 
@@ -83,5 +83,5 @@ func report(dur time.Duration, ctx *context.Context, vec *prometheus.SummaryVec)
 	status := ctx.Output.Status
 	ptn := ctx.Input.GetData("RouterPattern").(string)
 	ms := dur / time.Millisecond
-	vec.WithLabelValues(ptn, ctx.Input.Method(), strconv.Itoa(status), strconv.Itoa(int(ms))).Observe(float64(ms))
+	vec.WithLabelValues(ptn, ctx.Input.Method(), strconv.Itoa(status)).Observe(float64(ms))
 }
diff --git a/task/task.go b/task/task.go
index 00cbbfa7..2ea34f24 100644
--- a/task/task.go
+++ b/task/task.go
@@ -157,6 +157,9 @@ func (t *Task) GetSpec(context.Context) string {
 func (t *Task) GetStatus(context.Context) string {
 	var str string
 	for _, v := range t.Errlist {
+		if v == nil {
+			continue
+		}
 		str += v.t.String() + ":" + v.errinfo + "<br>"
 	}
 	return str
diff --git a/task/task_test.go b/task/task_test.go
index 2cb807ce..5e117cbd 100644
--- a/task/task_test.go
+++ b/task/task_test.go
@@ -36,9 +36,11 @@ func TestParse(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	assert.Equal(t, "0/30 * * * * *", tk.GetSpec(context.Background()))
 	m.AddTask("taska", tk)
 	m.StartTask()
 	time.Sleep(3 * time.Second)
+	assert.True(t, len(tk.GetStatus(context.Background())) == 0)
 	m.StopTask()
 }