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
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
|
package cgroups
import (
"bufio"
"fmt"
"io"
"io/ioutil"
"os"
"path/filepath"
"strconv"
"strings"
"syscall"
"golang.org/x/sys/unix"
specs "github.com/opencontainers/runtime-spec/specs-go"
)
func NewMemory(root string) *memoryController {
return &memoryController{
root: filepath.Join(root, string(Memory)),
}
}
type memoryController struct {
root string
}
func (m *memoryController) Name() Name {
return Memory
}
func (m *memoryController) Path(path string) string {
return filepath.Join(m.root, path)
}
func (m *memoryController) Create(path string, resources *specs.LinuxResources) error {
if err := os.MkdirAll(m.Path(path), defaultDirPerm); err != nil {
return err
}
if resources.Memory == nil {
return nil
}
if resources.Memory.Kernel != nil {
// Check if kernel memory is enabled
// We have to limit the kernel memory here as it won't be accounted at all
// until a limit is set on the cgroup and limit cannot be set once the
// cgroup has children, or if there are already tasks in the cgroup.
for _, i := range []int64{1, -1} {
if err := ioutil.WriteFile(
filepath.Join(m.Path(path), "memory.kmem.limit_in_bytes"),
[]byte(strconv.FormatInt(i, 10)),
defaultFilePerm,
); err != nil {
return checkEBUSY(err)
}
}
}
return m.set(path, getMemorySettings(resources))
}
func (m *memoryController) Update(path string, resources *specs.LinuxResources) error {
if resources.Memory == nil {
return nil
}
g := func(v *int64) bool {
return v != nil && *v > 0
}
settings := getMemorySettings(resources)
if g(resources.Memory.Limit) && g(resources.Memory.Swap) {
// if the updated swap value is larger than the current memory limit set the swap changes first
// then set the memory limit as swap must always be larger than the current limit
current, err := readUint(filepath.Join(m.Path(path), "memory.limit_in_bytes"))
if err != nil {
return err
}
if current < uint64(*resources.Memory.Swap) {
settings[0], settings[1] = settings[1], settings[0]
}
}
return m.set(path, settings)
}
func (m *memoryController) Stat(path string, stats *Metrics) error {
f, err := os.Open(filepath.Join(m.Path(path), "memory.stat"))
if err != nil {
return err
}
defer f.Close()
stats.Memory = &MemoryStat{
Usage: &MemoryEntry{},
Swap: &MemoryEntry{},
Kernel: &MemoryEntry{},
KernelTCP: &MemoryEntry{},
}
if err := m.parseStats(f, stats.Memory); err != nil {
return err
}
for _, t := range []struct {
module string
entry *MemoryEntry
}{
{
module: "",
entry: stats.Memory.Usage,
},
{
module: "memsw",
entry: stats.Memory.Swap,
},
{
module: "kmem",
entry: stats.Memory.Kernel,
},
{
module: "kmem.tcp",
entry: stats.Memory.KernelTCP,
},
} {
for _, tt := range []struct {
name string
value *uint64
}{
{
name: "usage_in_bytes",
value: &t.entry.Usage,
},
{
name: "max_usage_in_bytes",
value: &t.entry.Max,
},
{
name: "failcnt",
value: &t.entry.Failcnt,
},
{
name: "limit_in_bytes",
value: &t.entry.Limit,
},
} {
parts := []string{"memory"}
if t.module != "" {
parts = append(parts, t.module)
}
parts = append(parts, tt.name)
v, err := readUint(filepath.Join(m.Path(path), strings.Join(parts, ".")))
if err != nil {
return err
}
*tt.value = v
}
}
return nil
}
func (m *memoryController) OOMEventFD(path string) (uintptr, error) {
root := m.Path(path)
f, err := os.Open(filepath.Join(root, "memory.oom_control"))
if err != nil {
return 0, err
}
defer f.Close()
fd, _, serr := unix.RawSyscall(unix.SYS_EVENTFD2, 0, unix.EFD_CLOEXEC, 0)
if serr != 0 {
return 0, serr
}
if err := writeEventFD(root, f.Fd(), fd); err != nil {
unix.Close(int(fd))
return 0, err
}
return fd, nil
}
func writeEventFD(root string, cfd, efd uintptr) error {
f, err := os.OpenFile(filepath.Join(root, "cgroup.event_control"), os.O_WRONLY, 0)
if err != nil {
return err
}
_, err = f.WriteString(fmt.Sprintf("%d %d", efd, cfd))
f.Close()
return err
}
func (m *memoryController) parseStats(r io.Reader, stat *MemoryStat) error {
var (
raw = make(map[string]uint64)
sc = bufio.NewScanner(r)
line int
)
for sc.Scan() {
if err := sc.Err(); err != nil {
return err
}
key, v, err := parseKV(sc.Text())
if err != nil {
return fmt.Errorf("%d: %v", line, err)
}
raw[key] = v
line++
}
stat.Cache = raw["cache"]
stat.RSS = raw["rss"]
stat.RSSHuge = raw["rss_huge"]
stat.MappedFile = raw["mapped_file"]
stat.Dirty = raw["dirty"]
stat.Writeback = raw["writeback"]
stat.PgPgIn = raw["pgpgin"]
stat.PgPgOut = raw["pgpgout"]
stat.PgFault = raw["pgfault"]
stat.PgMajFault = raw["pgmajfault"]
stat.InactiveAnon = raw["inactive_anon"]
stat.ActiveAnon = raw["active_anon"]
stat.InactiveFile = raw["inactive_file"]
stat.ActiveFile = raw["active_file"]
stat.Unevictable = raw["unevictable"]
stat.HierarchicalMemoryLimit = raw["hierarchical_memory_limit"]
stat.HierarchicalSwapLimit = raw["hierarchical_memsw_limit"]
stat.TotalCache = raw["total_cache"]
stat.TotalRSS = raw["total_rss"]
stat.TotalRSSHuge = raw["total_rss_huge"]
stat.TotalMappedFile = raw["total_mapped_file"]
stat.TotalDirty = raw["total_dirty"]
stat.TotalWriteback = raw["total_writeback"]
stat.TotalPgPgIn = raw["total_pgpgin"]
stat.TotalPgPgOut = raw["total_pgpgout"]
stat.TotalPgFault = raw["total_pgfault"]
stat.TotalPgMajFault = raw["total_pgmajfault"]
stat.TotalInactiveAnon = raw["total_inactive_anon"]
stat.TotalActiveAnon = raw["total_active_anon"]
stat.TotalInactiveFile = raw["total_inactive_file"]
stat.TotalActiveFile = raw["total_active_file"]
stat.TotalUnevictable = raw["total_unevictable"]
return nil
}
func (m *memoryController) set(path string, settings []memorySettings) error {
for _, t := range settings {
if t.value != nil {
if err := ioutil.WriteFile(
filepath.Join(m.Path(path), fmt.Sprintf("memory.%s", t.name)),
[]byte(strconv.FormatInt(*t.value, 10)),
defaultFilePerm,
); err != nil {
return err
}
}
}
return nil
}
type memorySettings struct {
name string
value *int64
}
func getMemorySettings(resources *specs.LinuxResources) []memorySettings {
mem := resources.Memory
var swappiness *int64
if mem.Swappiness != nil {
v := int64(*mem.Swappiness)
swappiness = &v
}
return []memorySettings{
{
name: "limit_in_bytes",
value: mem.Limit,
},
{
name: "memsw.limit_in_bytes",
value: mem.Swap,
},
{
name: "kmem.limit_in_bytes",
value: mem.Kernel,
},
{
name: "kmem.tcp.limit_in_bytes",
value: mem.KernelTCP,
},
{
name: "oom_control",
value: getOomControlValue(mem),
},
{
name: "swappiness",
value: swappiness,
},
}
}
func checkEBUSY(err error) error {
if pathErr, ok := err.(*os.PathError); ok {
if errNo, ok := pathErr.Err.(syscall.Errno); ok {
if errNo == unix.EBUSY {
return fmt.Errorf(
"failed to set memory.kmem.limit_in_bytes, because either tasks have already joined this cgroup or it has children")
}
}
}
return err
}
func getOomControlValue(mem *specs.LinuxMemory) *int64 {
if mem.DisableOOMKiller != nil && *mem.DisableOOMKiller {
i := int64(1)
return &i
}
return nil
}
|
