utils

Documentation

Index

• Constants
• func CreateDir(path string) error
• func GetHostName() (string, error)
• func GetNowMs() int64
• func IsNil(i interface{}) bool
• func MurmurHash64A(data []byte) (h uint64)
• func Write(strs ...string) (string, error)
• type Cell
  • func (cell *Cell) Reset()
• type SlidingWindow
  • func NewSlidingWindow(size int64, cellIntervalMs int64) *SlidingWindow
  • func (sw *SlidingWindow) GetActualDurationMs(nowMs int64) int64
  • func (sw *SlidingWindow) GetHit(nowMs int64, metricName string) int64
  • func (sw *SlidingWindow) GetHits(nowMs int64, metricNames ...string) map[string]int64
  • func (sw *SlidingWindow) GetNowHits(nowMs int64, metricNames ...string) map[string]int64
  • func (sw *SlidingWindow) Hit(nowMs int64, metricNames ...string)

Constants

const (
	BIG_M = 0xc6a4a7935bd1e995
	BIG_R = 47
	SEED  = 0x1234ABCD
)

Functions

func CreateDir

func CreateDir(path string) error

func GetHostName

func GetHostName() (string, error)

func GetNowMs

func GetNowMs() int64

timestamp in ms

func IsNil

func IsNil(i interface{}) bool

func MurmurHash64A

func MurmurHash64A(data []byte) (h uint64)

murmur hash function. When the number of unique elements is 10000000, the hash distribution is as follows: |--------------------||--------------------| | bucket | num || bucket | num | |--------------------||--------------------| | 0 | 1000095 || 5 | 999697 | |--------------------||--------------------| | 1 | 1000449 || 6 | 1000249 | |--------------------||--------------------| | 2 | 999580 || 7 | 1000917 | |--------------------||--------------------| | 3 | 999182 || 8 | 1000388 | |--------------------||--------------------| | 4 | 998817 || 9 | 1000626 | |--------------------||--------------------|

E(X) = 389275.8

func Write

func Write(strs ...string) (string, error)

直接拼接字符串,如果缓冲变得太大，Write会采用错误值 ErrTooLarge 引发panic

Types

type Cell

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

func (*Cell) Reset

func (cell *Cell) Reset()

type SlidingWindow

type SlidingWindow struct {
	Size           int64
	CellIntervalMs int64
	Cells          []*Cell // invariant: len(Cells) == Size.
}

func NewSlidingWindow

func NewSlidingWindow(size int64, cellIntervalMs int64) *SlidingWindow

func (*SlidingWindow) GetActualDurationMs

func (sw *SlidingWindow) GetActualDurationMs(nowMs int64) int64

func (*SlidingWindow) GetHit

func (sw *SlidingWindow) GetHit(nowMs int64, metricName string) int64

func (*SlidingWindow) GetHits

func (sw *SlidingWindow) GetHits(nowMs int64, metricNames ...string) map[string]int64

func (*SlidingWindow) GetNowHits

func (sw *SlidingWindow) GetNowHits(nowMs int64, metricNames ...string) map[string]int64

func (*SlidingWindow) Hit

func (sw *SlidingWindow) Hit(nowMs int64, metricNames ...string)

一次动作(如请求)，记为一次 Hit。