pkg/cgroups/fs/memory.go
Victor Marmol 38d7599ca3 Add memory usage and max usage stats.
Docker-DCO-1.1-Signed-off-by: Victor Marmol <vmarmol@google.com> (github: vmarmol)
2014-04-25 02:51:28 +00:00

90 lines
2 KiB
Go

package fs
import (
"bufio"
"fmt"
"os"
"path/filepath"
"strconv"
)
type memoryGroup struct {
}
func (s *memoryGroup) Set(d *data) error {
dir, err := d.join("memory")
// only return an error for memory if it was not specified
if err != nil && (d.c.Memory != 0 || d.c.MemoryReservation != 0 || d.c.MemorySwap != 0) {
return err
}
defer func() {
if err != nil {
os.RemoveAll(dir)
}
}()
// Only set values if some config was specified.
if d.c.Memory != 0 || d.c.MemoryReservation != 0 || d.c.MemorySwap != 0 {
if d.c.Memory != 0 {
if err := writeFile(dir, "memory.limit_in_bytes", strconv.FormatInt(d.c.Memory, 10)); err != nil {
return err
}
}
if d.c.MemoryReservation != 0 {
if err := writeFile(dir, "memory.soft_limit_in_bytes", strconv.FormatInt(d.c.MemoryReservation, 10)); err != nil {
return err
}
}
// By default, MemorySwap is set to twice the size of RAM.
// If you want to omit MemorySwap, set it to `-1'.
if d.c.MemorySwap != -1 {
if err := writeFile(dir, "memory.memsw.limit_in_bytes", strconv.FormatInt(d.c.Memory*2, 10)); err != nil {
return err
}
}
}
return nil
}
func (s *memoryGroup) Remove(d *data) error {
return removePath(d.path("memory"))
}
func (s *memoryGroup) Stats(d *data) (map[string]float64, error) {
paramData := make(map[string]float64)
path, err := d.path("memory")
if err != nil {
return nil, err
}
// Set stats from memory.stat.
statsFile, err := os.Open(filepath.Join(path, "memory.stat"))
if err != nil {
return nil, err
}
defer statsFile.Close()
sc := bufio.NewScanner(statsFile)
for sc.Scan() {
t, v, err := getCgroupParamKeyValue(sc.Text())
if err != nil {
return nil, err
}
paramData[t] = v
}
// Set memory usage and max historical usage.
params := []string{
"usage_in_bytes",
"max_usage_in_bytes",
}
for _, param := range params {
value, err := getCgroupParamFloat64(path, fmt.Sprintf("memory.%s", param))
if err != nil {
return nil, err
}
paramData[param] = value
}
return paramData, nil
}