counters

Documentation

Index

• Constants
• type AtomicCounter
  • func NewAtomicCounter(reader *Reader, counterId int32) (*AtomicCounter, error)
  • func (ac *AtomicCounter) Get() int64
  • func (ac *AtomicCounter) GetWeak() int64
  • func (ac *AtomicCounter) Label() string
  • func (ac *AtomicCounter) Set(value int64)
  • func (ac *AtomicCounter) SetWeak(value int64)
  • func (ac *AtomicCounter) State() int32
• type Counter
• type MetaDataFlyweight
  • func InitAndWrapMetaData(buf *atomic.Buffer, offset int, toDriverBufLen int32, toClientBufLen int32, ...) *MetaDataFlyweight
  • func MapFile(filename string) (*MetaDataFlyweight, *memmap.File, error)
  • func (m *MetaDataFlyweight) Wrap(buf *atomic.Buffer, offset int) flyweight.Flyweight
• type ReadableCounter
  • func NewReadableCounter(reader *Reader, counterId int32) (*ReadableCounter, error)
  • func NewReadableRegisteredCounter(reader *Reader, registrationId int64, counterId int32) (*ReadableCounter, error)
  • func (rc *ReadableCounter) Close()
  • func (rc *ReadableCounter) Get() int64
  • func (rc *ReadableCounter) GetWeak() int64
  • func (rc *ReadableCounter) IsClosed() bool
  • func (rc *ReadableCounter) Label() string
  • func (rc *ReadableCounter) State() int32
• type Reader
  • func NewReader(values, metaData *atomic.Buffer) *Reader
  • func (reader *Reader) FindCounter(typeId int32, keyFilter func(keyBuffer *atomic.Buffer) bool) int32
  • func (reader *Reader) GetCounterOwnerId(counterId int32) int64
  • func (reader *Reader) GetCounterRegistrationId(counterId int32) int64
  • func (reader *Reader) GetCounterTypeId(counterId int32) int32
  • func (reader *Reader) GetCounterValue(counterId int32) int64
  • func (reader *Reader) GetKeyPartInt32(counterId int32, offset int32) (int32, error)
  • func (reader *Reader) GetKeyPartInt64(counterId int32, offset int32) (int64, error)
  • func (reader *Reader) GetKeyPartString(counterId int32, offset int32) (string, error)
  • func (reader *Reader) IsCounterAllocated(counterId int32) bool
  • func (reader *Reader) Scan(cb func(Counter))
  • func (reader *Reader) ScanForType(typeId int32, callback func(counterId int32, keyBuffer *atomic.Buffer) bool)

Constants

const (
	CncFile                 = "cnc.dat"
	CurrentCncVersion int32 = 512 // util.SemanticVersionCompose(0, 2, 0)
)

const CounterLength = util.CacheLineLength * 2

const FreeForReuseDeadlineOffset = TypeIdOffset + util.SizeOfInt32

FreeForReuseDeadlineOffset is the offset in the record at which the deadline (in milliseconds) for when counter may be reused.

const FullLabelLength = util.CacheLineLength * 6

const KeyOffset = FreeForReuseDeadlineOffset + util.SizeOfInt64

const LabelOffset = util.CacheLineLength * 2

const MaxKeyLength = (util.CacheLineLength * 2) - (util.SizeOfInt32 * 2) - util.SizeOfInt64

const MaxLabelLength = FullLabelLength - util.SizeOfInt32

const MetadataLength = LabelOffset + FullLabelLength

const NullCounterId = int32(-1)

const OwnerIdOffset = RegistrationIdOffset + util.SizeOfInt64

const RecordAllocated int32 = 1

const RecordReclaimed int32 = -1

const RecordUnused int32 = 0

const RegistrationIdOffset = util.SizeOfInt64

const TypeIdOffset = util.SizeOfInt32

Types

type AtomicCounter

type AtomicCounter struct {
	Reader    *Reader
	CounterId int32
	// contains filtered or unexported fields
}

func NewAtomicCounter

func NewAtomicCounter(reader *Reader, counterId int32) (*AtomicCounter, error)

func (*AtomicCounter) Get

func (ac *AtomicCounter) Get() int64

func (*AtomicCounter) GetWeak

func (ac *AtomicCounter) GetWeak() int64

func (*AtomicCounter) Label

func (ac *AtomicCounter) Label() string

func (*AtomicCounter) Set

func (ac *AtomicCounter) Set(value int64)

func (*AtomicCounter) SetWeak

func (ac *AtomicCounter) SetWeak(value int64)

func (*AtomicCounter) State

func (ac *AtomicCounter) State() int32

type Counter

type Counter struct {
	Id     int32
	TypeId int32
	Value  int64
	Label  string
}

type MetaDataFlyweight

type MetaDataFlyweight struct {
	flyweight.FWBase

	CncVersion flyweight.Int32Field

	ClientLivenessTo     flyweight.Int64Field
	DriverStartTimestamp flyweight.Int64Field
	DriverPid            flyweight.Int64Field

	ToDriverBuf  flyweight.RawDataField
	ToClientsBuf flyweight.RawDataField
	MetaDataBuf  flyweight.RawDataField
	ValuesBuf    flyweight.RawDataField
	ErrorBuf     flyweight.RawDataField
	// contains filtered or unexported fields
}

*

• Description of the command and control file used between driver and clients.
• <p>
• File Layout
• <pre>
• +-----------------------------+
• | Meta Data |
• +-----------------------------+
• | to-driver Buffer |
• +-----------------------------+
• | to-clients Buffer |
• +-----------------------------+
• | Counters Metadata Buffer |
• +-----------------------------+
• | Counters Values Buffer |
• +-----------------------------+
• | Error Log |
• +-----------------------------+
• </pre>
• <p>
• Meta Data Layout (CnC Version 0.2.0 => 512)
• <pre>
• 0 1 2 3
• 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
• +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
• | Aeron CnC Version |
• +---------------------------------------------------------------+
• | to-driver buffer length |
• +---------------------------------------------------------------+
• | to-clients buffer length |
• +---------------------------------------------------------------+
• | Counters Metadata buffer length |
• +---------------------------------------------------------------+
• | Counters Values buffer length |
• +---------------------------------------------------------------+
• | Error Log buffer length |
• +---------------------------------------------------------------+
• | Client Liveness Timeout |
• | |
• +---------------------------------------------------------------+
• | Driver Start Timestamp |
• | |
• +---------------------------------------------------------------+
• | Driver PID |
• | |
• +---------------------------------------------------------------+
• </pre> *
• See also <a href="https://github.com/real-logic/aeron/blob/master/aeron-client/src/main/cpp/CncFileDescriptor.h">CncFileDescriptor.h</a>.

func InitAndWrapMetaData

func InitAndWrapMetaData(buf *atomic.Buffer, offset int, toDriverBufLen int32, toClientBufLen int32,
	metadataBufLen int32, valuesBufLen int32, errorLogLen int32) *MetaDataFlyweight

InitAndWrapMetaData is a test method to inject the desired values into the buffer, then wrap it as a MetaDataFlyweight.

func MapFile

func MapFile(filename string) (*MetaDataFlyweight, *memmap.File, error)

func (*MetaDataFlyweight) Wrap

func (m *MetaDataFlyweight) Wrap(buf *atomic.Buffer, offset int) flyweight.Flyweight

type ReadableCounter

type ReadableCounter struct {
	Reader         *Reader
	RegistrationId int64
	CounterId      int32
	// contains filtered or unexported fields
}

func NewReadableCounter

func NewReadableCounter(reader *Reader, counterId int32) (*ReadableCounter, error)

func NewReadableRegisteredCounter

func NewReadableRegisteredCounter(reader *Reader, registrationId int64, counterId int32) (*ReadableCounter, error)

func (*ReadableCounter) Close

func (rc *ReadableCounter) Close()

func (*ReadableCounter) Get

func (rc *ReadableCounter) Get() int64

func (*ReadableCounter) GetWeak

func (rc *ReadableCounter) GetWeak() int64

func (*ReadableCounter) IsClosed

func (rc *ReadableCounter) IsClosed() bool

func (*ReadableCounter) Label

func (rc *ReadableCounter) Label() string

func (*ReadableCounter) State

func (rc *ReadableCounter) State() int32

type Reader

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

func NewReader

func NewReader(values, metaData *atomic.Buffer) *Reader

func (*Reader) FindCounter

func (reader *Reader) FindCounter(typeId int32, keyFilter func(keyBuffer *atomic.Buffer) bool) int32

func (*Reader) GetCounterOwnerId

func (reader *Reader) GetCounterOwnerId(counterId int32) int64

func (*Reader) GetCounterRegistrationId

func (reader *Reader) GetCounterRegistrationId(counterId int32) int64

func (*Reader) GetCounterTypeId

func (reader *Reader) GetCounterTypeId(counterId int32) int32

GetCounterTypeId returns the type id for a counter.

func (*Reader) GetCounterValue

func (reader *Reader) GetCounterValue(counterId int32) int64

GetCounterValue returns the value of the given counter id (as a volatile read).

func (*Reader) GetKeyPartInt32

func (reader *Reader) GetKeyPartInt32(counterId int32, offset int32) (int32, error)

GetKeyPartInt32 returns an int32 portion of the key at the specified offset

func (*Reader) GetKeyPartInt64

func (reader *Reader) GetKeyPartInt64(counterId int32, offset int32) (int64, error)

GetKeyPartInt64 returns an int64 portion of the key at the specified offset

func (*Reader) GetKeyPartString

func (reader *Reader) GetKeyPartString(counterId int32, offset int32) (string, error)

GetKeyPartString returns a string portion of the key, assuming the string is prefixed by its length (as an 32-bit int) at the specified offset.

func (*Reader) IsCounterAllocated

func (reader *Reader) IsCounterAllocated(counterId int32) bool

func (*Reader) Scan

func (reader *Reader) Scan(cb func(Counter))

func (*Reader) ScanForType

func (reader *Reader) ScanForType(typeId int32, callback func(counterId int32, keyBuffer *atomic.Buffer) bool)