summaryrefslogtreecommitdiff
path: root/vendor/github.com/prometheus/procfs/stat.go
blob: 6d8727541e40e578628726d7aa2c6ad68bc36fb0 (plain)
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
207
208
209
210
211
212
213
214
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
240
241
242
243
244
// 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.

package procfs

import (
	"bufio"
	"bytes"
	"fmt"
	"io"
	"strconv"
	"strings"

	"github.com/prometheus/procfs/internal/fs"
	"github.com/prometheus/procfs/internal/util"
)

// 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 {
		return CPUStat{}, -1, fmt.Errorf("couldn't parse %q (cpu): %w", line, err)
	}
	if count == 0 {
		return CPUStat{}, -1, fmt.Errorf("couldn't parse %q (cpu): 0 elements parsed", line)
	}

	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 {
		return CPUStat{}, -1, fmt.Errorf("couldn't parse %q (cpu/cpuid): %w", line, err)
	}

	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 {
		return SoftIRQStat{}, 0, fmt.Errorf("couldn't parse %q (softirq): %w", line, err)
	}

	return softIRQStat, total, nil
}

// 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
func (fs FS) NewStat() (Stat, error) {
	return fs.Stat()
}

// 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)
	if err != nil {
		return Stat{}, err
	}

	stat := Stat{}

	scanner := bufio.NewScanner(bytes.NewReader(data))
	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 {
				return Stat{}, fmt.Errorf("couldn't parse %q (btime): %w", parts[1], err)
			}
		case parts[0] == "intr":
			if stat.IRQTotal, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
				return Stat{}, fmt.Errorf("couldn't parse %q (intr): %w", parts[1], err)
			}
			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 {
					return Stat{}, fmt.Errorf("couldn't parse %q (intr%d): %w", count, i, err)
				}
			}
		case parts[0] == "ctxt":
			if stat.ContextSwitches, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
				return Stat{}, fmt.Errorf("couldn't parse %q (ctxt): %w", parts[1], err)
			}
		case parts[0] == "processes":
			if stat.ProcessCreated, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
				return Stat{}, fmt.Errorf("couldn't parse %q (processes): %w", parts[1], err)
			}
		case parts[0] == "procs_running":
			if stat.ProcessesRunning, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
				return Stat{}, fmt.Errorf("couldn't parse %q (procs_running): %w", parts[1], err)
			}
		case parts[0] == "procs_blocked":
			if stat.ProcessesBlocked, err = strconv.ParseUint(parts[1], 10, 64); err != nil {
				return Stat{}, fmt.Errorf("couldn't parse %q (procs_blocked): %w", parts[1], err)
			}
		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 {
		return Stat{}, fmt.Errorf("couldn't parse %q: %w", fileName, err)
	}

	return stat, nil
}