diff options
Diffstat (limited to 'src/cmd/trace/pprof.go')
-rw-r--r-- | src/cmd/trace/pprof.go | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/src/cmd/trace/pprof.go b/src/cmd/trace/pprof.go new file mode 100644 index 0000000000..9e6f277978 --- /dev/null +++ b/src/cmd/trace/pprof.go @@ -0,0 +1,162 @@ +// Copyright 2014 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. + +// Serving of pprof-like profiles. + +package main + +import ( + "bufio" + "fmt" + "internal/trace" + "io/ioutil" + "net/http" + "os" + "os/exec" +) + +func init() { + http.HandleFunc("/io", httpIO) + http.HandleFunc("/block", httpBlock) + http.HandleFunc("/syscall", httpSyscall) + http.HandleFunc("/sched", httpSched) +} + +// Record represents one entry in pprof-like profiles. +type Record struct { + stk []*trace.Frame + n uint64 + time int64 +} + +// httpIO serves IO pprof-like profile (time spent in IO wait). +func httpIO(w http.ResponseWriter, r *http.Request) { + events, err := parseEvents() + if err != nil { + http.Error(w, err.Error(), http.StatusInternalServerError) + return + } + prof := make(map[uint64]Record) + for _, ev := range events { + if ev.Type != trace.EvGoBlockNet || ev.Link == nil || ev.StkID == 0 || len(ev.Stk) == 0 { + continue + } + rec := prof[ev.StkID] + rec.stk = ev.Stk + rec.n++ + rec.time += ev.Link.Ts - ev.Ts + prof[ev.StkID] = rec + } + serveSVGProfile(w, r, prof) +} + +// httpBlock serves blocking pprof-like profile (time spent blocked on synchronization primitives). +func httpBlock(w http.ResponseWriter, r *http.Request) { + events, err := parseEvents() + if err != nil { + http.Error(w, err.Error(), http.StatusInternalServerError) + return + } + prof := make(map[uint64]Record) + for _, ev := range events { + switch ev.Type { + case trace.EvGoBlockSend, trace.EvGoBlockRecv, trace.EvGoBlockSelect, + trace.EvGoBlockSync, trace.EvGoBlockCond: + default: + continue + } + if ev.Link == nil || ev.StkID == 0 || len(ev.Stk) == 0 { + continue + } + rec := prof[ev.StkID] + rec.stk = ev.Stk + rec.n++ + rec.time += ev.Link.Ts - ev.Ts + prof[ev.StkID] = rec + } + serveSVGProfile(w, r, prof) +} + +// httpSyscall serves syscall pprof-like profile (time spent blocked in syscalls). +func httpSyscall(w http.ResponseWriter, r *http.Request) { + events, err := parseEvents() + if err != nil { + http.Error(w, err.Error(), http.StatusInternalServerError) + return + } + prof := make(map[uint64]Record) + for _, ev := range events { + if ev.Type != trace.EvGoSysCall || ev.Link == nil || ev.StkID == 0 || len(ev.Stk) == 0 { + continue + } + rec := prof[ev.StkID] + rec.stk = ev.Stk + rec.n++ + rec.time += ev.Link.Ts - ev.Ts + prof[ev.StkID] = rec + } + serveSVGProfile(w, r, prof) +} + +// httpSched serves scheduler latency pprof-like profile +// (time between a goroutine become runnable and actually scheduled for execution). +func httpSched(w http.ResponseWriter, r *http.Request) { + events, err := parseEvents() + if err != nil { + http.Error(w, err.Error(), http.StatusInternalServerError) + return + } + prof := make(map[uint64]Record) + for _, ev := range events { + if (ev.Type != trace.EvGoUnblock && ev.Type != trace.EvGoCreate) || + ev.Link == nil || ev.StkID == 0 || len(ev.Stk) == 0 { + continue + } + rec := prof[ev.StkID] + rec.stk = ev.Stk + rec.n++ + rec.time += ev.Link.Ts - ev.Ts + prof[ev.StkID] = rec + } + serveSVGProfile(w, r, prof) +} + +// 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) { + blockf, err := ioutil.TempFile("", "block") + if err != nil { + http.Error(w, fmt.Sprintf("failed to create temp file: %v", err), http.StatusInternalServerError) + return + } + defer os.Remove(blockf.Name()) + blockb := bufio.NewWriter(blockf) + fmt.Fprintf(blockb, "--- contention:\ncycles/second=1000000000\n") + for _, rec := range prof { + fmt.Fprintf(blockb, "%v %v @", rec.time, rec.n) + for _, f := range rec.stk { + fmt.Fprintf(blockb, " 0x%x", f.PC) + } + fmt.Fprintf(blockb, "\n") + } + err = blockb.Flush() + if err != nil { + http.Error(w, fmt.Sprintf("failed to flush temp file: %v", err), http.StatusInternalServerError) + return + } + err = blockf.Close() + if err != nil { + http.Error(w, fmt.Sprintf("failed to close temp file: %v", err), http.StatusInternalServerError) + return + } + + svgFilename := blockf.Name() + ".svg" + _, err = exec.Command("go", "tool", "pprof", "-svg", "-output", svgFilename, programBinary, blockf.Name()).CombinedOutput() + if err != nil { + http.Error(w, fmt.Sprintf("failed to execute go tool pprof: %v", err), http.StatusInternalServerError) + return + } + defer os.Remove(svgFilename) + w.Header().Set("Content-Type", "image/svg+xml") + http.ServeFile(w, r, svgFilename) +} |