cgroups

Documentation

Index

• func EnterPid(cgroupPaths map[string]string, pid int) error
• func FindCgroupMountpoint(subsystem string) (string, error)
• func GetAllSubsystems() ([]string, error)
• func GetInitCgroupDir(subsystem string) (string, error)
• func GetThisCgroupDir(subsystem string) (string, error)
• func IsNotFound(err error) bool
• func NewNotFoundError(sub string) error
• func ParseCgroupFile(subsystem string, r io.Reader) (string, error)
• func ReadProcsFile(dir string) ([]int, error)
• func RemovePaths(paths map[string]string) (err error)
• type BlkioStatEntry
• type BlkioStats
• type Cgroup
• type CpuStats
• type CpuUsage
• type FreezerState
• type MemoryStats
• type Mount
  • func GetCgroupMounts() ([]Mount, error)
  • func (m Mount) GetThisCgroupDir() (string, error)
• type NotFoundError
  • func (e *NotFoundError) Error() string
• type Stats
  • func NewStats() *Stats
• type ThrottlingData

Functions

func EnterPid

func EnterPid(cgroupPaths map[string]string, pid int) error

func FindCgroupMountpoint

func FindCgroupMountpoint(subsystem string) (string, error)

https://www.kernel.org/doc/Documentation/cgroups/cgroups.txt

func GetAllSubsystems

func GetAllSubsystems() ([]string, error)

Returns all the cgroup subsystems supported by the kernel

func GetInitCgroupDir

func GetInitCgroupDir(subsystem string) (string, error)

func GetThisCgroupDir

func GetThisCgroupDir(subsystem string) (string, error)

Returns the relative path to the cgroup docker is running in.

func IsNotFound

func IsNotFound(err error) bool

func NewNotFoundError

func NewNotFoundError(sub string) error

func ParseCgroupFile

func ParseCgroupFile(subsystem string, r io.Reader) (string, error)

func ReadProcsFile

func ReadProcsFile(dir string) ([]int, error)

func RemovePaths

func RemovePaths(paths map[string]string) (err error)

RemovePaths iterates over the provided paths removing them. If an error is encountered the removal proceeds and the first error is returned to ensure a partial removal is not possible.

Types

type BlkioStatEntry

type BlkioStatEntry struct {
	Major uint64 `json:"major,omitempty"`
	Minor uint64 `json:"minor,omitempty"`
	Op    string `json:"op,omitempty"`
	Value uint64 `json:"value,omitempty"`
}

type BlkioStats

type BlkioStats struct {
	// number of bytes tranferred to and from the block device
	IoServiceBytesRecursive []BlkioStatEntry `json:"io_service_bytes_recursive,omitempty"`
	IoServicedRecursive     []BlkioStatEntry `json:"io_serviced_recursive,omitempty"`
	IoQueuedRecursive       []BlkioStatEntry `json:"io_queue_recursive,omitempty"`
	IoServiceTimeRecursive  []BlkioStatEntry `json:"io_service_time_recursive,omitempty"`
	IoWaitTimeRecursive     []BlkioStatEntry `json:"io_wait_time_recursive,omitempty"`
	IoMergedRecursive       []BlkioStatEntry `json:"io_merged_recursive,omitempty"`
	IoTimeRecursive         []BlkioStatEntry `json:"io_time_recursive,omitempty"`
	SectorsRecursive        []BlkioStatEntry `json:"sectors_recursive,omitempty"`
}

type Cgroup

type Cgroup struct {
	Name   string `json:"name,omitempty"`
	Parent string `json:"parent,omitempty"` // name of parent cgroup or slice

	AllowAllDevices   bool              `json:"allow_all_devices,omitempty"` // If this is true allow access to any kind of device within the container.  If false, allow access only to devices explicitly listed in the allowed_devices list.
	AllowedDevices    []*devices.Device `json:"allowed_devices,omitempty"`
	Memory            int64             `json:"memory,omitempty"`             // Memory limit (in bytes)
	MemoryReservation int64             `json:"memory_reservation,omitempty"` // Memory reservation or soft_limit (in bytes)
	MemorySwap        int64             `json:"memory_swap,omitempty"`        // Total memory usage (memory + swap); set `-1' to disable swap
	CpuShares         int64             `json:"cpu_shares,omitempty"`         // CPU shares (relative weight vs. other containers)
	CpuQuota          int64             `json:"cpu_quota,omitempty"`          // CPU hardcap limit (in usecs). Allowed cpu time in a given period.
	CpuPeriod         int64             `json:"cpu_period,omitempty"`         // CPU period to be used for hardcapping (in usecs). 0 to use system default.
	CpusetCpus        string            `json:"cpuset_cpus,omitempty"`        // CPU to use
	Freezer           FreezerState      `json:"freezer,omitempty"`            // set the freeze value for the process
	Slice             string            `json:"slice,omitempty"`              // Parent slice to use for systemd
}

type CpuStats

type CpuStats struct {
	CpuUsage       CpuUsage       `json:"cpu_usage,omitempty"`
	ThrottlingData ThrottlingData `json:"throttling_data,omitempty"`
}

type CpuUsage

type CpuUsage struct {
	// Total CPU time consumed.
	// Units: nanoseconds.
	TotalUsage uint64 `json:"total_usage,omitempty"`
	// Total CPU time consumed per core.
	// Units: nanoseconds.
	PercpuUsage []uint64 `json:"percpu_usage,omitempty"`
	// Time spent by tasks of the cgroup in kernel mode.
	// Units: nanoseconds.
	UsageInKernelmode uint64 `json:"usage_in_kernelmode"`
	// Time spent by tasks of the cgroup in user mode.
	// Units: nanoseconds.
	UsageInUsermode uint64 `json:"usage_in_usermode"`
}

All CPU stats are aggregate since container inception.

type FreezerState

type FreezerState string

const (
	Undefined FreezerState = ""
	Frozen    FreezerState = "FROZEN"
	Thawed    FreezerState = "THAWED"
)

type MemoryStats

type MemoryStats struct {
	// current res_counter usage for memory
	Usage uint64 `json:"usage,omitempty"`
	// maximum usage ever recorded.
	MaxUsage uint64 `json:"max_usage,omitempty"`
	// TODO(vishh): Export these as stronger types.
	// all the stats exported via memory.stat.
	Stats map[string]uint64 `json:"stats,omitempty"`
	// number of times memory usage hits limits.
	Failcnt uint64 `json:"failcnt"`
}

type Mount

type Mount struct {
	Mountpoint string
	Subsystems []string
}

func GetCgroupMounts

func GetCgroupMounts() ([]Mount, error)

func (Mount) GetThisCgroupDir

func (m Mount) GetThisCgroupDir() (string, error)

type NotFoundError

type NotFoundError struct {
	Subsystem string
}

func (*NotFoundError) Error

func (e *NotFoundError) Error() string

type Stats

type Stats struct {
	CpuStats    CpuStats    `json:"cpu_stats,omitempty"`
	MemoryStats MemoryStats `json:"memory_stats,omitempty"`
	BlkioStats  BlkioStats  `json:"blkio_stats,omitempty"`
}

func NewStats

func NewStats() *Stats

type ThrottlingData

type ThrottlingData struct {
	// Number of periods with throttling active
	Periods uint64 `json:"periods,omitempty"`
	// Number of periods when the container hit its throttling limit.
	ThrottledPeriods uint64 `json:"throttled_periods,omitempty"`
	// Aggregate time the container was throttled for in nanoseconds.
	ThrottledTime uint64 `json:"throttled_time,omitempty"`
}