Struct WriterHealth 

pub struct WriterHealth {
    pub stats: WriterStats,
    pub unaccounted: u64,
    pub shed: u64,
    pub queue_depth: usize,
    pub queue_capacity: usize,
    pub last_ingest_at: Option<Timestamp>,
}

A reading of the writer’s accounting health, safe to serialise.

Note what lost does not tell you at runtime: the steady-state path retries an unavailable sink forever, so an outage declares nothing lost until the final flush gives up. A healthy-but-cut-off process reports lost == 0 for its whole life. The one steady-state loss is a batch the sink refuses (a permanent error, such as an accounting overflow): it is counted in lost and dropped at once, because replaying it would earn the same refusal forever and block every event behind it. The leading indicators are WriterHealth::ingest_age, a queue_depth approaching queue_capacity, and stats.rejected — which the sink has already refused, and which is bounded billing loss.

Fields

stats: WriterStats

The same accounting and coverage diagnostics a clean shutdown returns, read live.

unaccounted: u64

Charges in the queue with no billing outcome yet.

shed: u64

Requests refused for want of queue capacity (INVARIANTS.md GL-8).

queue_depth: usize

Slots currently held by queued events and outstanding permits.

queue_capacity: usize

The shed point: queue_depth reaching this denies the next request.

last_ingest_at: Option<Timestamp>

When the sink last answered, or None if it never has.

Implementations

impl WriterHealth

pub fn ingest_age(&self, now: Timestamp) -> Option<SignedDuration>

How long since the sink last answered — the signal that separates “no traffic” from “the sink has been unreachable for twenty minutes”. None while no ingest has ever succeeded, which is also the state of a freshly started process.

Trait Implementations

impl Clone for WriterHealth

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for WriterHealth

impl Debug for WriterHealth

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

Formats the value using the given formatter.

impl Eq for WriterHealth

impl PartialEq for WriterHealth

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for WriterHealth