cgroups

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

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"`
}

type HugetlbStats struct {
	// current res_counter usage for hugetlb
	Usage uint64 `json:"usage,omitempty"`
	// maximum usage ever recorded.
	MaxUsage uint64 `json:"max_usage,omitempty"`
	// number of times hugetlb usage allocation failure.
	Failcnt uint64 `json:"failcnt"`
}

type Manager interface {
	// Applies cgroup configuration to the process with the specified pid
	Apply(pid int) error

	// Returns the PIDs inside the cgroup set
	GetPids() ([]int, error)

	// Returns the PIDs inside the cgroup set & all sub-cgroups
	GetAllPids() ([]int, error)

	// Returns statistics for the cgroup set
	GetStats() (*Stats, error)

	// Toggles the freezer cgroup according with specified state
	Freeze(state configs.FreezerState) error

	// Destroys the cgroup set
	Destroy() error

	// Returns cgroup paths to save in a state file and to be able to
	// restore the object later.
	GetPaths() map[string]string

	// Sets the cgroup as configured.
	Set(container *configs.Config) error
}

type MemoryData struct {
	Usage    uint64 `json:"usage,omitempty"`
	MaxUsage uint64 `json:"max_usage,omitempty"`
	Failcnt  uint64 `json:"failcnt"`
	Limit    uint64 `json:"limit"`
}

type MemoryStats struct {
	// memory used for cache
	Cache uint64 `json:"cache,omitempty"`
	// usage of memory
	Usage MemoryData `json:"usage,omitempty"`
	// usage of memory + swap
	SwapUsage MemoryData `json:"swap_usage,omitempty"`
	// usage of kernel memory
	KernelUsage MemoryData `json:"kernel_usage,omitempty"`
	// usage of kernel TCP memory
	KernelTCPUsage MemoryData `json:"kernel_tcp_usage,omitempty"`
	// if true, memory usage is accounted for throughout a hierarchy of cgroups.
	UseHierarchy bool `json:"use_hierarchy"`

	Stats map[string]uint64 `json:"stats,omitempty"`
}

type Mount struct {
	Mountpoint string
	Root       string
	Subsystems []string
}

type NotFoundError struct {
	Subsystem string
}

type PidsStats struct {
	// number of pids in the cgroup
	Current uint64 `json:"current,omitempty"`
	// active pids hard limit
	Limit uint64 `json:"limit,omitempty"`
}

type Stats struct {
	CpuStats    CpuStats    `json:"cpu_stats,omitempty"`
	MemoryStats MemoryStats `json:"memory_stats,omitempty"`
	PidsStats   PidsStats   `json:"pids_stats,omitempty"`
	BlkioStats  BlkioStats  `json:"blkio_stats,omitempty"`
	// the map is in the format "size of hugepage: stats of the hugepage"
	HugetlbStats map[string]HugetlbStats `json:"hugetlb_stats,omitempty"`
}

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"`
}