Struct Lsn 

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

Monotonic log sequence number.

LSN 0 is reserved for “empty / never written” so a snapshot’s wal_lsn = 0 cannot be mistaken for “I checkpointed at the very first record”. Allocators advance from 1.

Internally an LSN is opaque: callers only rely on the total order. The representation is left as a single u64 for now; a future change to a (segment_id, offset) packing is non-breaking because every consumer goes through these accessors.

Implementations

impl Lsn

pub const ZERO: Lsn

pub const fn new(value: u64) -> Self

pub const fn raw(self) -> u64

pub const fn is_zero(self) -> bool

pub fn checked_next(self) -> Option<Self>

Returns the next LSN, or None if the counter is exhausted.

pub fn next(self) -> Self

Returns the next LSN, saturating at u64::MAX.

Production WAL allocation uses Self::checked_next so exhaustion can surface as a structured error. This convenience method is kept non-panicking for low-level callers and tests that only need simple monotonic advancement.

Trait Implementations

impl Clone for Lsn

fn clone(&self) -> Lsn

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Lsn

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Lsn

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Lsn

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

Formats the value using the given formatter.

impl From<Lsn> for u64

fn from(value: Lsn) -> Self

Converts to this type from the input type.

impl From<u64> for Lsn

fn from(value: u64) -> Self

Converts to this type from the input type.

impl Hash for Lsn

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 Lsn

fn cmp(&self, other: &Lsn) -> 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 Lsn

fn eq(&self, other: &Lsn) -> 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 Lsn

fn partial_cmp(&self, other: &Lsn) -> 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 Serialize for Lsn

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for Lsn

impl Eq for Lsn

impl StructuralPartialEq for Lsn