ringbuf

Documentation

Index

• Variables
• func InitMetrics(namespace string, constLabels prometheus.Labels, labelNames []string)
• type Entry
• type EntryList
• type NewEntryF
• type Ring
  • func New(count int, newf NewEntryF, desc string, labels prometheus.Labels) *Ring
  • func (r *Ring) Close()
  • func (r *Ring) Read(entries EntryList, block bool) (int, bool)
  • func (r *Ring) Write(entries EntryList, block bool) (int, bool)

Variables

var MaxEntries *prometheus.GaugeVec

var ReadCalls *prometheus.CounterVec

var ReadEntries *prometheus.HistogramVec

var ReadsBlocked *prometheus.CounterVec

var UsedEntries *prometheus.GaugeVec

var WriteCalls *prometheus.CounterVec

var WriteEntries *prometheus.HistogramVec

var WritesBlocked *prometheus.CounterVec

Functions

func InitMetrics

func InitMetrics(namespace string, constLabels prometheus.Labels, labelNames []string)

Types

type Entry

type Entry interface{}

type EntryList

type EntryList []Entry

type NewEntryF

type NewEntryF func() interface{}

type Ring

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

Ring is a classic generic ring buffer on top of a fixed-sized slice. It is thread-safe.

func New

func New(count int, newf NewEntryF, desc string, labels prometheus.Labels) *Ring

New allocates a new Ring instance, with capacity for count entries. If newf is non-nil, it is called count times to pre-allocate the entries. labels are attached to the prometheus metrics, and desc is added as an extra label. N.B. InitMetrics must be called before the first New call.

func (*Ring) Close

func (r *Ring) Close()

Close closes the ring buffer, and causes all blocked readers/writers to be notified.

func (*Ring) Read

func (r *Ring) Read(entries EntryList, block bool) (int, bool)

Read copies entries from the internal ring buffer. If block is true, then Read will block until it is able to read at least one entry (or the Ring is closed). Otherwise it will return immediately if there's no entries available for reading. Returns the number of entries read, or -1 if the RingBuf is closed, and a bool indicating if the read blocked.

func (*Ring) Write

func (r *Ring) Write(entries EntryList, block bool) (int, bool)

Write copies entries to the internal ring buffer. If block is true, then Write will block until it is able to write at least one entry (or the Ring is closed). Otherwise it will return immediately if there's on space left for writing. Returns the number of entries written, or -1 if the RingBuf is closed, and a bool indicating if the write blocked.