From d7a27b8e847e99eae8262fccb713ffe7e29deccf Mon Sep 17 00:00:00 2001
From: Jhon Honce <jhonce@redhat.com>
Date: Tue, 21 Apr 2020 15:30:57 -0700
Subject: Instrumentation to answer #5765

* currently wired to localhost:8888 to prevent access from off machine

Signed-off-by: Jhon Honce <jhonce@redhat.com>
---
 cmd/podman/system/info.go |  2 +-
 pkg/api/server/server.go  | 41 ++++++++++++++++++++++++++++++-----------
 2 files changed, 31 insertions(+), 12 deletions(-)

diff --git a/cmd/podman/system/info.go b/cmd/podman/system/info.go
index 8e014a91b..8b36ef549 100644
--- a/cmd/podman/system/info.go
+++ b/cmd/podman/system/info.go
@@ -7,8 +7,8 @@ import (
 
 	"github.com/containers/libpod/cmd/podman/registry"
 	"github.com/containers/libpod/pkg/domain/entities"
+	"github.com/ghodss/yaml"
 	"github.com/spf13/cobra"
-	"gopkg.in/yaml.v2"
 )
 
 var (
diff --git a/pkg/api/server/server.go b/pkg/api/server/server.go
index 9576fd437..ce2d152e0 100644
--- a/pkg/api/server/server.go
+++ b/pkg/api/server/server.go
@@ -8,6 +8,7 @@ import (
 	"os"
 	"os/signal"
 	"runtime"
+	goRuntime "runtime"
 	"strings"
 	"sync"
 	"syscall"
@@ -30,6 +31,7 @@ type APIServer struct {
 	net.Listener                    // mux for routing HTTP API calls to libpod routines
 	context.CancelFunc              // Stop APIServer
 	idleTracker        *IdleTracker // Track connections to support idle shutdown
+	pprof              *http.Server // Sidecar http server for providing performance data
 }
 
 // Number of seconds to wait for next request, if exceeded shutdown server
@@ -145,6 +147,20 @@ func (s *APIServer) Serve() error {
 		_ = s.Shutdown()
 	}()
 
+	if logrus.IsLevelEnabled(logrus.DebugLevel) {
+		go func() {
+			pprofMux := mux.NewRouter()
+			pprofMux.PathPrefix("/debug/pprof").Handler(http.DefaultServeMux)
+			goRuntime.SetMutexProfileFraction(1)
+			goRuntime.SetBlockProfileRate(1)
+			s.pprof = &http.Server{Addr: "localhost:8888", Handler: pprofMux}
+			err := s.pprof.ListenAndServe()
+			if err != nil && err != http.ErrServerClosed {
+				logrus.Warn("Profiler Service failed: " + err.Error())
+			}
+		}()
+	}
+
 	go func() {
 		err := s.Server.Serve(s.Listener)
 		if err != nil && err != http.ErrServerClosed {
@@ -166,26 +182,29 @@ func (s *APIServer) Serve() error {
 
 // Shutdown is a clean shutdown waiting on existing clients
 func (s *APIServer) Shutdown() error {
-	if logrus.IsLevelEnabled(logrus.DebugLevel) {
-		_, file, line, _ := runtime.Caller(1)
-		logrus.Debugf("APIServer.Shutdown by %s:%d, %d/%d connection(s)",
-			file, line, s.idleTracker.ActiveConnections(), s.idleTracker.TotalConnections())
-	}
-
-	// Duration == 0 flags no auto-shutdown of the server
-	if s.idleTracker.Duration == 0 {
-		logrus.Debug("APIServer.Shutdown ignored as Duration == 0")
+	if s.idleTracker.Duration == UnlimitedServiceDuration {
+		logrus.Debug("APIServer.Shutdown ignored as Duration is UnlimitedService.")
 		return nil
 	}
 
-	// Gracefully shutdown server, duration of wait same as idle window
+	// Gracefully shutdown server(s), duration of wait same as idle window
 	// TODO: Should we really wait the idle window for shutdown?
 	ctx, cancel := context.WithTimeout(context.Background(), s.idleTracker.Duration)
 	defer cancel()
+
+	if logrus.IsLevelEnabled(logrus.DebugLevel) {
+		_, file, line, _ := runtime.Caller(1)
+		logrus.Debugf("APIServer.Shutdown by %s:%d, %d/%d connection(s)",
+			file, line, s.idleTracker.ActiveConnections(), s.idleTracker.TotalConnections())
+		if err := s.pprof.Shutdown(ctx); err != nil {
+			logrus.Warn("Failed to cleanly shutdown pprof Server: " + err.Error())
+		}
+	}
+
 	go func() {
 		err := s.Server.Shutdown(ctx)
 		if err != nil && err != context.Canceled && err != http.ErrServerClosed {
-			logrus.Errorf("Failed to cleanly shutdown APIServer: %s", err.Error())
+			logrus.Error("Failed to cleanly shutdown APIServer: " + err.Error())
 		}
 	}()
 	<-ctx.Done()
-- 
cgit v1.2.3-54-g00ecf