stat.go 7.13 KB
Newer Older
ale's avatar
ale committed
1
2
3
4
5
6
7
8
9
10
11
12
13
// Copyright 2018 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

ale's avatar
ale committed
14
15
16
17
package procfs

import (
	"bufio"
18
	"bytes"
ale's avatar
ale committed
19
20
21
22
	"fmt"
	"io"
	"strconv"
	"strings"
23
24
25

	"github.com/prometheus/procfs/internal/fs"
	"github.com/prometheus/procfs/internal/util"
ale's avatar
ale committed
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
)

// CPUStat shows how much time the cpu spend in various stages.
type CPUStat struct {
	User      float64
	Nice      float64
	System    float64
	Idle      float64
	Iowait    float64
	IRQ       float64
	SoftIRQ   float64
	Steal     float64
	Guest     float64
	GuestNice float64
}

// SoftIRQStat represent the softirq statistics as exported in the procfs stat file.
// A nice introduction can be found at https://0xax.gitbooks.io/linux-insides/content/interrupts/interrupts-9.html
// It is possible to get per-cpu stats by reading /proc/softirqs
type SoftIRQStat struct {
	Hi          uint64
	Timer       uint64
	NetTx       uint64
	NetRx       uint64
	Block       uint64
	BlockIoPoll uint64
	Tasklet     uint64
	Sched       uint64
	Hrtimer     uint64
	Rcu         uint64
}

// Stat represents kernel/system statistics.
type Stat struct {
	// Boot time in seconds since the Epoch.
	BootTime uint64
	// Summed up cpu statistics.
	CPUTotal CPUStat
	// Per-CPU statistics.
	CPU []CPUStat
	// Number of times interrupts were handled, which contains numbered and unnumbered IRQs.
	IRQTotal uint64
	// Number of times a numbered IRQ was triggered.
	IRQ []uint64
	// Number of times a context switch happened.
	ContextSwitches uint64
	// Number of times a process was created.
	ProcessCreated uint64
	// Number of processes currently running.
	ProcessesRunning uint64
	// Number of processes currently blocked (waiting for IO).
	ProcessesBlocked uint64
	// Number of times a softirq was scheduled.
	SoftIRQTotal uint64
	// Detailed softirq statistics.
	SoftIRQ SoftIRQStat
}

// Parse a cpu statistics line and returns the CPUStat struct plus the cpu id (or -1 for the overall sum).
func parseCPUStat(line string) (CPUStat, int64, error) {
	cpuStat := CPUStat{}
	var cpu string

	count, err := fmt.Sscanf(line, "%s %f %f %f %f %f %f %f %f %f %f",
		&cpu,
		&cpuStat.User, &cpuStat.Nice, &cpuStat.System, &cpuStat.Idle,
		&cpuStat.Iowait, &cpuStat.IRQ, &cpuStat.SoftIRQ, &cpuStat.Steal,
		&cpuStat.Guest, &cpuStat.GuestNice)

	if err != nil && err != io.EOF {
96
		return CPUStat{}, -1, fmt.Errorf("couldn't parse %q (cpu): %w", line, err)
ale's avatar
ale committed
97
98
	}
	if count == 0 {
99
		return CPUStat{}, -1, fmt.Errorf("couldn't parse %q (cpu): 0 elements parsed", line)
ale's avatar
ale committed
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
	}

	cpuStat.User /= userHZ
	cpuStat.Nice /= userHZ
	cpuStat.System /= userHZ
	cpuStat.Idle /= userHZ
	cpuStat.Iowait /= userHZ
	cpuStat.IRQ /= userHZ
	cpuStat.SoftIRQ /= userHZ
	cpuStat.Steal /= userHZ
	cpuStat.Guest /= userHZ
	cpuStat.GuestNice /= userHZ

	if cpu == "cpu" {
		return cpuStat, -1, nil
	}

	cpuID, err := strconv.ParseInt(cpu[3:], 10, 64)
	if err != nil {
119
		return CPUStat{}, -1, fmt.Errorf("couldn't parse %q (cpu/cpuid): %w", line, err)
ale's avatar
ale committed
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
	}

	return cpuStat, cpuID, nil
}

// Parse a softirq line.
func parseSoftIRQStat(line string) (SoftIRQStat, uint64, error) {
	softIRQStat := SoftIRQStat{}
	var total uint64
	var prefix string

	_, err := fmt.Sscanf(line, "%s %d %d %d %d %d %d %d %d %d %d %d",
		&prefix, &total,
		&softIRQStat.Hi, &softIRQStat.Timer, &softIRQStat.NetTx, &softIRQStat.NetRx,
		&softIRQStat.Block, &softIRQStat.BlockIoPoll,
		&softIRQStat.Tasklet, &softIRQStat.Sched,
		&softIRQStat.Hrtimer, &softIRQStat.Rcu)

	if err != nil {
139
		return SoftIRQStat{}, 0, fmt.Errorf("couldn't parse %q (softirq): %w", line, err)
ale's avatar
ale committed
140
141
142
143
144
	}

	return softIRQStat, total, nil
}

145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
// NewStat returns information about current cpu/process statistics.
// See https://www.kernel.org/doc/Documentation/filesystems/proc.txt
//
// Deprecated: use fs.Stat() instead
func NewStat() (Stat, error) {
	fs, err := NewFS(fs.DefaultProcMountPoint)
	if err != nil {
		return Stat{}, err
	}
	return fs.Stat()
}

// NewStat returns information about current cpu/process statistics.
// See https://www.kernel.org/doc/Documentation/filesystems/proc.txt
//
// Deprecated: use fs.Stat() instead
ale's avatar
ale committed
161
func (fs FS) NewStat() (Stat, error) {
162
163
	return fs.Stat()
}
ale's avatar
ale committed
164

165
166
167
168
169
// Stat returns information about current cpu/process statistics.
// See https://www.kernel.org/doc/Documentation/filesystems/proc.txt
func (fs FS) Stat() (Stat, error) {
	fileName := fs.proc.Path("stat")
	data, err := util.ReadFileNoStat(fileName)
ale's avatar
ale committed
170
171
172
173
174
175
	if err != nil {
		return Stat{}, err
	}

	stat := Stat{}

176
	scanner := bufio.NewScanner(bytes.NewReader(data))
ale's avatar
ale committed
177
178
179
180
181
182
183
184
185
186
	for scanner.Scan() {
		line := scanner.Text()
		parts := strings.Fields(scanner.Text())
		// require at least <key> <value>
		if len(parts) < 2 {
			continue
		}
		switch {
		case parts[0] == "btime":
			if stat.BootTime, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
187
				return Stat{}, fmt.Errorf("couldn't parse %q (btime): %w", parts[1], err)
ale's avatar
ale committed
188
189
190
			}
		case parts[0] == "intr":
			if stat.IRQTotal, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
191
				return Stat{}, fmt.Errorf("couldn't parse %q (intr): %w", parts[1], err)
ale's avatar
ale committed
192
193
194
195
196
			}
			numberedIRQs := parts[2:]
			stat.IRQ = make([]uint64, len(numberedIRQs))
			for i, count := range numberedIRQs {
				if stat.IRQ[i], err = strconv.ParseUint(count, 10, 64); err != nil {
197
					return Stat{}, fmt.Errorf("couldn't parse %q (intr%d): %w", count, i, err)
ale's avatar
ale committed
198
199
200
201
				}
			}
		case parts[0] == "ctxt":
			if stat.ContextSwitches, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
202
				return Stat{}, fmt.Errorf("couldn't parse %q (ctxt): %w", parts[1], err)
ale's avatar
ale committed
203
204
205
			}
		case parts[0] == "processes":
			if stat.ProcessCreated, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
206
				return Stat{}, fmt.Errorf("couldn't parse %q (processes): %w", parts[1], err)
ale's avatar
ale committed
207
208
209
			}
		case parts[0] == "procs_running":
			if stat.ProcessesRunning, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
210
				return Stat{}, fmt.Errorf("couldn't parse %q (procs_running): %w", parts[1], err)
ale's avatar
ale committed
211
212
213
			}
		case parts[0] == "procs_blocked":
			if stat.ProcessesBlocked, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
214
				return Stat{}, fmt.Errorf("couldn't parse %q (procs_blocked): %w", parts[1], err)
ale's avatar
ale committed
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
			}
		case parts[0] == "softirq":
			softIRQStats, total, err := parseSoftIRQStat(line)
			if err != nil {
				return Stat{}, err
			}
			stat.SoftIRQTotal = total
			stat.SoftIRQ = softIRQStats
		case strings.HasPrefix(parts[0], "cpu"):
			cpuStat, cpuID, err := parseCPUStat(line)
			if err != nil {
				return Stat{}, err
			}
			if cpuID == -1 {
				stat.CPUTotal = cpuStat
			} else {
				for int64(len(stat.CPU)) <= cpuID {
					stat.CPU = append(stat.CPU, CPUStat{})
				}
				stat.CPU[cpuID] = cpuStat
			}
		}
	}

	if err := scanner.Err(); err != nil {
240
		return Stat{}, fmt.Errorf("couldn't parse %q: %w", fileName, err)
ale's avatar
ale committed
241
242
243
244
	}

	return stat, nil
}