Struct Pick 

pub struct Pick { /* private fields */ }

A chosen instance plus a guard tracking its load (ADR 000035). For least_request the guard holds the selected instance’s incremented active-request count and decrements it on drop — on EVERY forward return path (success, retry, transport error) and on each retry hand-off, because replacing the Pick drops the previous guard. For round-robin / maglev the guard is a no-op. Derefs to the instance so callers read address() / is_healthy() directly.

Implementations

impl Pick

pub fn instance(&self) -> &Arc<UpstreamInstance>

The chosen instance (for pick_excluding / record_outcome / passive-failure book-keeping).

Methods from Deref<Target = UpstreamInstance>

pub fn address(&self) -> &str

This instance’s host:port.

pub fn weight(&self) -> u32

This instance’s load-balancing weight (ADR 000035), >= 1.

pub fn in_flight(&self) -> usize

Current active forwarded-request count to this instance (ADR 000035) — the least-request load signal. Lock-free read.

pub fn is_healthy(&self) -> bool

Whether this instance is currently in rotation. Lock-free — the round-robin hot path.

pub fn is_outlier_ejected(&self, now_ms: u64) -> bool

Whether this instance is currently outlier-ejected at now_ms (ADR 000032). Lock-free — the pick hot path. The ejection auto-expires when its window passes (no probe needed); this is a distinct axis from is_healthy (an instance can be probe-healthy yet outlier-ejected).

pub fn record_probe_success(&self)

Record a successful active probe (a 2xx within the timeout). Promotes a pessimistic / ejected instance once it reaches its threshold — one success the first time ever, healthy_threshold after a later eject — and resets the consecutive-failure streak.

pub fn record_probe_failure(&self)

Record a failed active probe (non-2xx, timeout, or connect error).

pub fn record_passive_failure(&self)

Record a passive failure — a real forwarded request that could not even connect to this instance (ADR 000017). It demotes exactly like a probe failure, but can only ever demote: an ejected instance receives no traffic, so only the active prober restores it.

Trait Implementations

impl Deref for Pick

type Target = UpstreamInstance

The resulting type after dereferencing.

fn deref(&self) -> &UpstreamInstance

Dereferences the value.