pkg/libcontainer/cgroups/fs/memory.go
Vishnu Kannan c7135d73d3 Added a new method cgroups.GetStats() which will return a cgroups.Stats object which will contain all the available cgroup Stats.
Remove old Stats interface in libcontainers cgroups package.
Changed Stats to use unit64 instead of int64 to prevent integer overflow issues.
Updated unit tests.

Docker-DCO-1.1-Signed-off-by: Vishnu Kannan <vishnuk@google.com> (github: vishh)
2014-05-29 20:16:49 +00:00

89 lines
2 KiB
Go

package fs
import (
"bufio"
"os"
"path/filepath"
"strconv"
"github.com/dotcloud/docker/pkg/libcontainer/cgroups"
)
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) GetStats(d *data, stats *cgroups.Stats) error {
path, err := d.path("memory")
if err != nil {
return err
}
// Set stats from memory.stat.
statsFile, err := os.Open(filepath.Join(path, "memory.stat"))
if err != nil {
return err
}
defer statsFile.Close()
sc := bufio.NewScanner(statsFile)
for sc.Scan() {
t, v, err := getCgroupParamKeyValue(sc.Text())
if err != nil {
return err
}
stats.MemoryStats.Stats[t] = v
}
// Set memory usage and max historical usage.
value, err := getCgroupParamInt(path, "memory.usage_in_bytes")
if err != nil {
return err
}
stats.MemoryStats.Usage = value
value, err = getCgroupParamInt(path, "memory.max_usage_in_bytes")
if err != nil {
return err
}
stats.MemoryStats.MaxUsage = value
return nil
}