cmd/trace: gracefully handle empty profiles

Return a meaningful message when a profile is empty. Also rename "IO blocking" to "Network blocking", currently only network blocking is captured. Fixes #11098 Change-Id: Ib6f1292b8ade4805756fcb6696ba1fca8f9f39a9 Reviewed-on: https://go-review.googlesource.com/11243Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

cmd/trace: gracefully handle empty profiles
Return a meaningful message when a profile is empty. Also rename "IO blocking" to "Network blocking", currently only network blocking is captured. Fixes #11098 Change-Id: Ib6f1292b8ade4805756fcb6696ba1fca8f9f39a9 Reviewed-on: https://go-review.googlesource.com/11243Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
1b269463 · Dmitry Vyukov · e72f5f67 · 1b269463 · 1b269463
Commit 1b269463 authored Jun 18, 2015 by Dmitry Vyukov
Hide whitespace changes
Inline Side-by-side

Showing with 5 additions and 1 deletion

main.go src/cmd/trace/main.go +1 -1

pprof.go src/cmd/trace/pprof.go +4 -0

No files found.
--- a/src/cmd/trace/main.go
+++ b/src/cmd/trace/main.go
@@ -124,7 +124,7 @@ var templMain = []byte(`
 <body>
 <a href="/trace">View trace</a><br>
 <a href="/goroutines">Goroutine analysis</a><br>
-<a href="/io">IO blocking profile</a><br>
+<a href="/io">Network blocking profile</a><br>
 <a href="/block">Synchronization blocking profile</a><br>
 <a href="/syscall">Syscall blocking profile</a><br>
 <a href="/sched">Scheduler latency profile</a><br>

--- a/src/cmd/trace/pprof.go
+++ b/src/cmd/trace/pprof.go
@@ -124,6 +124,10 @@ func httpSched(w http.ResponseWriter, r *http.Request) {

 // generateSVGProfile generates pprof-like profile stored in prof and writes in to w.
 func serveSVGProfile(w http.ResponseWriter, r *http.Request, prof map[uint64]Record) {
+	if len(prof) == 0 {
+		http.Error(w, "The profile is empty", http.StatusNotFound)
+		return
+	}
 	blockf, err := ioutil.TempFile("", "block")
 	if err != nil {
 		http.Error(w, fmt.Sprintf("failed to create temp file: %v", err), http.StatusInternalServerError)