aboutsummaryrefslogtreecommitdiffstats
path: root/internal/debug/api.go
blob: 01126b41bfd93768792b626a6a5edfc8e5510889 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

// Package debug interfaces Go runtime debugging facilities.
// This package is mostly glue code making these facilities available
// through the CLI and RPC subsystem. If you want to use them from Go code,
// use package runtime instead.
package debug

import (
    "errors"
    "fmt"
    "io"
    "os"
    "os/user"
    "path/filepath"
    "runtime"
    "runtime/debug"
    "runtime/pprof"
    "strings"
    "sync"
    "time"

    "github.com/ethereum/go-ethereum/log"
)

// Handler is the global debugging handler.
var Handler = new(HandlerT)

// HandlerT implements the debugging API.
// Do not create values of this type, use the one
// in the Handler variable instead.
type HandlerT struct {
    mu        sync.Mutex
    cpuW      io.WriteCloser
    cpuFile   string
    traceW    io.WriteCloser
    traceFile string
}

// Verbosity sets the log verbosity ceiling. The verbosity of individual packages
// and source files can be raised using Vmodule.
func (*HandlerT) Verbosity(level int) {
    glogger.Verbosity(log.Lvl(level))
}

// Vmodule sets the log verbosity pattern. See package log for details on the
// pattern syntax.
func (*HandlerT) Vmodule(pattern string) error {
    return glogger.Vmodule(pattern)
}

// BacktraceAt sets the log backtrace location. See package log for details on
// the pattern syntax.
func (*HandlerT) BacktraceAt(location string) error {
    return glogger.BacktraceAt(location)
}

// MemStats returns detailed runtime memory statistics.
func (*HandlerT) MemStats() *runtime.MemStats {
    s := new(runtime.MemStats)
    runtime.ReadMemStats(s)
    return s
}

// GcStats returns GC statistics.
func (*HandlerT) GcStats() *debug.GCStats {
    s := new(debug.GCStats)
    debug.ReadGCStats(s)
    return s
}

// CpuProfile turns on CPU profiling for nsec seconds and writes
// profile data to file.
func (h *HandlerT) CpuProfile(file string, nsec uint) error {
    if err := h.StartCPUProfile(file); err != nil {
        return err
    }
    time.Sleep(time.Duration(nsec) * time.Second)
    h.StopCPUProfile()
    return nil
}

// StartCPUProfile turns on CPU profiling, writing to the given file.
func (h *HandlerT) StartCPUProfile(file string) error {
    h.mu.Lock()
    defer h.mu.Unlock()
    if h.cpuW != nil {
        return errors.New("CPU profiling already in progress")
    }
    f, err := os.Create(expandHome(file))
    if err != nil {
        return err
    }
    if err := pprof.StartCPUProfile(f); err != nil {
        f.Close()
        return err
    }
    h.cpuW = f
    h.cpuFile = file
    log.Info(fmt.Sprint("CPU profiling started, writing to", h.cpuFile))
    return nil
}

// StopCPUProfile stops an ongoing CPU profile.
func (h *HandlerT) StopCPUProfile() error {
    h.mu.Lock()
    defer h.mu.Unlock()
    pprof.StopCPUProfile()
    if h.cpuW == nil {
        return errors.New("CPU profiling not in progress")
    }
    log.Info(fmt.Sprint("done writing CPU profile to", h.cpuFile))
    h.cpuW.Close()
    h.cpuW = nil
    h.cpuFile = ""
    return nil
}

// GoTrace turns on tracing for nsec seconds and writes
// trace data to file.
func (h *HandlerT) GoTrace(file string, nsec uint) error {
    if err := h.StartGoTrace(file); err != nil {
        return err
    }
    time.Sleep(time.Duration(nsec) * time.Second)
    h.StopGoTrace()
    return nil
}

// BlockProfile turns on CPU profiling for nsec seconds and writes
// profile data to file. It uses a profile rate of 1 for most accurate
// information. If a different rate is desired, set the rate
// and write the profile manually.
func (*HandlerT) BlockProfile(file string, nsec uint) error {
    runtime.SetBlockProfileRate(1)
    time.Sleep(time.Duration(nsec) * time.Second)
    defer runtime.SetBlockProfileRate(0)
    return writeProfile("block", file)
}

// SetBlockProfileRate sets the rate of goroutine block profile data collection.
// rate 0 disables block profiling.
func (*HandlerT) SetBlockProfileRate(rate int) {
    runtime.SetBlockProfileRate(rate)
}

// WriteBlockProfile writes a goroutine blocking profile to the given file.
func (*HandlerT) WriteBlockProfile(file string) error {
    return writeProfile("block", file)
}

// WriteMemProfile writes an allocation profile to the given file.
// Note that the profiling rate cannot be set through the API,
// it must be set on the command line.
func (*HandlerT) WriteMemProfile(file string) error {
    return writeProfile("heap", file)
}

// Stacks returns a printed representation of the stacks of all goroutines.
func (*HandlerT) Stacks() string {
    buf := make([]byte, 1024*1024)
    buf = buf[:runtime.Stack(buf, true)]
    return string(buf)
}

func writeProfile(name, file string) error {
    p := pprof.Lookup(name)
    log.Info(fmt.Sprintf("writing %d %s profile records to %s", p.Count(), name, file))
    f, err := os.Create(expandHome(file))
    if err != nil {
        return err
    }
    defer f.Close()
    return p.WriteTo(f, 0)
}

// expands home directory in file paths.
// ~someuser/tmp will not be expanded.
func expandHome(p string) string {
    if strings.HasPrefix(p, "~/") || strings.HasPrefix(p, "~\\") {
        home := os.Getenv("HOME")
        if home == "" {
            if usr, err := user.Current(); err == nil {
                home = usr.HomeDir
            }
        }
        if home != "" {
            p = home + p[1:]
        }
    }
    return filepath.Clean(p)
}