taskstats

README

taskstats

Package taskstats provides access to Linux's taskstats interface, for sending per-task, per-process, and cgroup statistics from the kernel to userspace.

For more information on taskstats, please see:

• https://www.kernel.org/doc/Documentation/accounting/cgroupstats.txt
• https://www.kernel.org/doc/Documentation/accounting/taskstats.txt
• https://www.kernel.org/doc/Documentation/accounting/taskstats-struct.txt
• https://andrestc.com/post/linux-delay-accounting/

Notes

• When instrumenting Go programs, use either the taskstats.Self() or taskstats.TGID() method. Using the PID() method on multithreaded programs, including Go programs, will produce inaccurate results.

• Access to taskstats requires that the application have at least CAP_NET_RAW capability (see capabilities(7)). Otherwise, the application must be run as root.

• If running the application in a container (e.g. via Docker), it cannot be run in a network namespace -- usually this means that host networking must be used.

MIT Licensed.

Documentation

Overview

Package taskstats provides access to Linux's taskstats interface, for sending per-task, per-process, and cgroup statistics from the kernel to userspace.

For more information on taskstats, please see:

• https://www.kernel.org/doc/Documentation/accounting/cgroupstats.txt
• https://www.kernel.org/doc/Documentation/accounting/taskstats.txt
• https://www.kernel.org/doc/Documentation/accounting/taskstats-struct.txt
• https://andrestc.com/post/linux-delay-accounting/

Index

• type CGroupStats
• type Client
  • func New() (*Client, error)
  • func (c *Client) CGroupStats(path string) (*CGroupStats, error)
  • func (c *Client) Close() error
  • func (c *Client) PID(pid int) (*Stats, error)
  • func (c *Client) Self() (*Stats, error)
  • func (c *Client) TGID(tgid int) (*Stats, error)
• type Stats

Types

type CGroupStats

type CGroupStats struct {
	Sleeping        uint64
	Running         uint64
	Stopped         uint64
	Uninterruptible uint64
	IOWait          uint64
}

CGroupStats contains statistics for tasks of an individual cgroup.

type Client

type Client struct {
	// contains filtered or unexported fields
}

A Client provides access to Linux taskstats information.

Some Client operations require elevated privileges.

func New

func New() (*Client, error)

New creates a new Client.

func (*Client) CGroupStats

func (c *Client) CGroupStats(path string) (*CGroupStats, error)

CGroupStats retrieves cgroup statistics for the cgroup specified by path. Path should be a CPU cgroup path found in sysfs, such as:

• /sys/fs/cgroup/cpu
• /sys/fs/cgroup/cpu/docker
• /sys/fs/cgroup/cpu/docker/(hexadecimal identifier)

func (*Client) Close

func (c *Client) Close() error

Close releases resources used by a Client.

func (*Client) PID

func (c *Client) PID(pid int) (*Stats, error)

PID retrieves statistics about a process, identified by its PID.

func (*Client) Self

func (c *Client) Self() (*Stats, error)

Self is a convenience method for retrieving statistics about the current process.

func (*Client) TGID

func (c *Client) TGID(tgid int) (*Stats, error)

TGID retrieves statistics about a thread group, identified by its TGID.

type Stats

type Stats struct {
	BeginTime           time.Time
	ElapsedTime         time.Duration
	UserCPUTime         time.Duration
	SystemCPUTime       time.Duration
	RealCPUTime         time.Duration
	MinorPageFaults     uint64
	MajorPageFaults     uint64
	CPUDelayCount       uint64
	CPUDelay            time.Duration
	BlockIODelayCount   uint64
	BlockIODelay        time.Duration
	SwapInDelayCount    uint64
	SwapInDelay         time.Duration
	FreePagesDelayCount uint64
	FreePagesDelay      time.Duration
}

Stats contains statistics for an individual task.