Struct Epoch 

pub struct Epoch(/* private fields */);

The placement-table generation a routing decision was resolved against.

Monotonically increasing. Stamped on every routed write so the sink can reject a stale-epoch write for a migrating partition (docs/06 §2).

Implementations

impl Epoch

pub const ZERO: Self

The initial epoch.

pub fn new(generation: u64) -> Self

Constructs an epoch from a raw generation number.

pub fn get(self) -> u64

Returns the raw generation number.

pub fn next(self) -> Self

Returns the next epoch. Saturates at u64::MAX rather than wrapping, so monotonicity (relied on by migration cutover, docs/06 INV-M2) can never be violated by overflow.

Trait Implementations

impl Clone for Epoch

fn clone(&self) -> Epoch

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Epoch

impl Debug for Epoch

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Epoch

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Epoch

impl Hash for Epoch

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Epoch

fn cmp(&self, other: &Epoch) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Epoch

fn eq(&self, other: &Epoch) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Epoch

fn partial_cmp(&self, other: &Epoch) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for Epoch