code review 5639059: runtime, pprof: add profiling of thread creation

src/pkg/net/http/pprof/pprof.go

 // Copyright 2010 The Go Authors.  All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 // Package pprof serves via its HTTP server runtime profiling data
 // in the format expected by the pprof visualization tool.
 // For more information about pprof, see
 // http://code.google.com/p/google-perftools/.
 //
 // The package is typically only imported for the side effect of
 // registering its HTTP handlers.
 // The handled paths all begin with /debug/pprof/.
 //
 // To use pprof, link this package into your program:
 //      import _ "http/pprof"
 //
 // Then use the pprof tool to look at the heap profile:
 //
-//      pprof http://localhost:6060/debug/pprof/heap
+//      go tool pprof http://localhost:6060/debug/pprof/heap
 //
 // Or to look at a 30-second CPU profile:
 //
-//      pprof http://localhost:6060/debug/pprof/profile
+//      go tool pprof http://localhost:6060/debug/pprof/profile
+//
+// Or to look at the thread creation profile:
+//
+//      go tool pprof http://localhost:6060/debug/pprof/thread
 //
 package pprof
 
 import (
         "bufio"
         "bytes"
         "fmt"
         "io"
         "net/http"
         "os"
         "runtime"
         "runtime/pprof"
         "strconv"
         "strings"
         "time"
 )
 
 func init() {
         http.Handle("/debug/pprof/cmdline", http.HandlerFunc(Cmdline))
         http.Handle("/debug/pprof/profile", http.HandlerFunc(Profile))
         http.Handle("/debug/pprof/heap", http.HandlerFunc(Heap))
         http.Handle("/debug/pprof/symbol", http.HandlerFunc(Symbol))
+        http.Handle("/debug/pprof/thread", http.HandlerFunc(Thread))
 }
 
 // Cmdline responds with the running program's
 // command line, with arguments separated by NUL bytes.
 // The package initialization registers it as /debug/pprof/cmdline.
 func Cmdline(w http.ResponseWriter, r *http.Request) {
         w.Header().Set("Content-Type", "text/plain; charset=utf-8")
         fmt.Fprintf(w, strings.Join(os.Args, "\x00"))
 }
 
 // Heap responds with the pprof-formatted heap profile.
 // The package initialization registers it as /debug/pprof/heap.
 func Heap(w http.ResponseWriter, r *http.Request) {
         w.Header().Set("Content-Type", "text/plain; charset=utf-8")
         pprof.WriteHeapProfile(w)
+}
+
+// Thread responds with the pprof-formatted thread creation profile.
+// The package initialization registers it as /debug/pprof/thread.
+func Thread(w http.ResponseWriter, r *http.Request) {
+        w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+        pprof.WriteThreadProfile(w)
 }
 
 // Profile responds with the pprof-formatted cpu profile.
 // The package initialization registers it as /debug/pprof/profile.
 func Profile(w http.ResponseWriter, r *http.Request) {
         sec, _ := strconv.ParseInt(r.FormValue("seconds"), 10, 64)
         if sec == 0 {
                 sec = 30
         }
 
@@ skipping 53 matching lines @@
                 if err != nil {
                         if err != io.EOF {
                                 fmt.Fprintf(&buf, "reading request: %v\n", err)
                         }
                         break
                 }
         }
 
         w.Write(buf.Bytes())
 }