Add pprof for galley (#10047)

* Enable pprof to galley

Signed-off-by: Chun Lin Yang <clyang@cn.ibm.com>

* start pprofile in 9094

Signed-off-by: Chun Lin Yang <clyang@cn.ibm.com>

galley/cmd/galley/cmd/root.go

@@ -52,6 +52,8 @@ func GetRootCmd(args []string, printf, fatalf shared.FormatFn) *cobra.Command {
 		livenessProbeController  probe.Controller
 		readinessProbeController probe.Controller
 		monitoringPort           uint
+		enableProfiling          bool
+		pprofPort                uint
 	)
 
 	rootCmd := &cobra.Command{
@@ -95,6 +97,11 @@ func GetRootCmd(args []string, printf, fatalf shared.FormatFn) *cobra.Command {
 			}
 			galleyStop := make(chan struct{})
 			go server.StartSelfMonitoring(galleyStop, monitoringPort)
+
+			if enableProfiling {
+				go server.StartProfiling(galleyStop, pprofPort)
+			}
+
 			go server.StartProbeCheck(livenessProbeController, readinessProbeController, galleyStop)
 			istiocmd.WaitSignal(galleyStop)
 
@@ -123,6 +130,9 @@ func GetRootCmd(args []string, printf, fatalf shared.FormatFn) *cobra.Command {
 		"Interval of updating file for the Galley readiness probe.")
 	rootCmd.PersistentFlags().UintVar(&monitoringPort, "monitoringPort", 9093,
 		"Port to use for exposing self-monitoring information")
+	rootCmd.PersistentFlags().UintVar(&pprofPort, "pprofPort", 9094, "Port to use for exposing profiling")
+	rootCmd.PersistentFlags().BoolVar(&enableProfiling, "enableProfiling", false,
+		"Enable profiling for Galley")
 
 	//server config
 	rootCmd.PersistentFlags().StringVarP(&serverArgs.APIAddress, "server-address", "", serverArgs.APIAddress,

galley/pkg/server/profiling.go

@@ -0,0 +1,58 @@
+// Copyright 2018 Istio 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.
+
+package server
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"net/http/pprof"
+)
+
+//StartProfiling start the profiling for Galley
+func StartProfiling(stop <-chan struct{}, port uint) {
+	lis, err := net.Listen("tcp", fmt.Sprintf(":%v", port))
+	if err != nil {
+		scope.Errorf("Unable to listen on profiling port %v: %v", port, err)
+		return
+	}
+
+	mux := http.NewServeMux()
+
+	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		//Redirect ROOT to /debug/pprof/ for convenience
+		http.Redirect(w, r, "/debug/pprof/", http.StatusSeeOther)
+	})
+	mux.HandleFunc("/debug/pprof/", pprof.Index)
+	mux.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
+	mux.HandleFunc("/debug/pprof/profile", pprof.Profile)
+	mux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
+	mux.HandleFunc("/debug/pprof/trace", pprof.Trace)
+
+	server := &http.Server{
+		Handler: mux,
+	}
+
+	go func() {
+		if err := server.Serve(lis); err != nil {
+			scope.Errorf("Profiling http server failed: %v", err)
+			return
+		}
+	}()
+
+	<-stop
+	err = server.Close()
+	scope.Debugf("Profiling http server terminated: %v", err)
+}