Struct RangeStreamProgress 

pub struct RangeStreamProgress {
    pub range_id: u64,
    pub applied_lsn: u64,
    pub streamed_lsn: u64,
    pub primary_lsn: u64,
}

Independent streaming progress for one range over the shared physical WAL.

All three LSNs are global WAL LSNs scoped to this range’s records: primary_lsn is the highest the primary has produced for the range, streamed_lsn the highest shipped to the follower, applied_lsn the highest the follower has durably applied. Their gaps give per-range lag that is independent of every other range riding the same WAL — the basis for per-range failover eligibility (issue #987).

Fields

range_id: u64

applied_lsn: u64

streamed_lsn: u64

primary_lsn: u64

Implementations

impl RangeStreamProgress

pub fn new(range_id: u64) -> RangeStreamProgress

pub fn apply_lag(&self) -> u64

Records this range still has to apply to match the primary frontier. Saturating so a follower transiently ahead of an observed frontier reports zero rather than underflowing.

pub fn stream_lag(&self) -> u64

Records produced for this range that have not yet been shipped.

pub fn is_caught_up(&self) -> bool

Whether the follower has applied everything the primary has produced for the range. False until a primary frontier has actually been observed, so an unknown range is never reported as caught up.

pub fn failover_eligible(&self, max_lag: u64) -> bool

Whether this range is within max_lag records of the primary — a per-range gate a later failover decision can consult. Requires an observed primary frontier.

pub fn encode_json(&self) -> Vec<u8>

pub fn decode_json( bytes: &[u8], ) -> Result<RangeStreamProgress, ReplicationPayloadError>

Trait Implementations

impl Clone for RangeStreamProgress

fn clone(&self) -> RangeStreamProgress

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for RangeStreamProgress

impl Debug for RangeStreamProgress

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

Formats the value using the given formatter.

impl Eq for RangeStreamProgress

impl PartialEq for RangeStreamProgress

fn eq(&self, other: &RangeStreamProgress) -> 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 StructuralPartialEq for RangeStreamProgress