package cgroups import ( "fmt" "os" "path/filepath" spec "github.com/opencontainers/runtime-spec/specs-go" ) type memHandler struct { } func getMemoryHandler() *memHandler { return &memHandler{} } // Apply set the specified constraints func (c *memHandler) Apply(ctr *CgroupControl, res *spec.LinuxResources) error { if res.Memory == nil { return nil } return fmt.Errorf("memory apply not implemented yet") } // Create the cgroup func (c *memHandler) Create(ctr *CgroupControl) (bool, error) { if ctr.cgroup2 { return false, fmt.Errorf("memory create not implemented for cgroup v2") } return ctr.createCgroupDirectory(Memory) } // Destroy the cgroup func (c *memHandler) Destroy(ctr *CgroupControl) error { return os.Remove(ctr.getCgroupv1Path(Memory)) } // Stat fills a metrics structure with usage stats for the controller func (c *memHandler) Stat(ctr *CgroupControl, m *Metrics) error { var err error usage := MemoryUsage{} var memoryRoot string filenames := map[string]string{} if ctr.cgroup2 { memoryRoot = filepath.Join(cgroupRoot, ctr.path) filenames["usage"] = "memory.current" filenames["limit"] = "memory.max" } else { memoryRoot = ctr.getCgroupv1Path(Memory) filenames["usage"] = "memory.usage_in_bytes" filenames["limit"] = "memory.limit_in_bytes" } usage.Usage, err = readFileAsUint64(filepath.Join(memoryRoot, filenames["usage"])) if err != nil { return err } usage.Limit, err = readFileAsUint64(filepath.Join(memoryRoot, filenames["limit"])) if err != nil { return err } m.Memory = MemoryMetrics{Usage: usage} return nil }