pub struct QueueAdmissionSnapshot {
pub current_depth: usize,
pub high_water: usize,
pub full_drops: u64,
pub fairness_drops: u64,
pub closed_drops: u64,
}Expand description
A consistent, count-only snapshot of one network-layer receive queue.
Counters belong to one receiver, not to a source MAC. A router’s local queue
is shared by all its ports. No payloads, source identities or per-source
totals are exposed. The three drop totals saturate at u64::MAX and attribute
each admission drop once, in Closed > fairness > Full order.
Separate APDU/control snapshots are not an atomic snapshot of both queues.
See the receive-queue contract and
QueueAdmissionCounters::snapshot for receiver kinds and lifetime.
Fields§
§current_depth: usizeItems currently queued (at most 256), excluding items already returned by
AdmissionReceiver::recv or AdmissionReceiver::try_recv. Close and
stop preserve depth until draining; dropping the receiver sets it to zero.
high_water: usizeGreatest queued depth since this receiver was created (at most 256). Draining, closing, stopping or dropping the receiver does not reset it.
full_drops: u64Arriving items dropped because the 256-item queue was full, after Closed
and any per-source fairness check; saturates at u64::MAX.
A fairness drop does not also increment this total.
fairness_drops: u64Arriving APDUs dropped by the tracked queue’s quota of 16 per source:
complete source MAC bytes for NetworkLayer, (ingress port network number,
source MAC bytes) for routers, never routed NPDU SNET/SADR. See the
source-key definitions.
Saturates at u64::MAX. Closed takes precedence; otherwise evaluated
before global Full, even when the queue has room. Always zero for control
queues, which have no per-source quota. This is a queue-wide total, not
a per-source counter.
closed_drops: u64Arriving items dropped because the receiver was closed or dropped;
saturates at u64::MAX. Takes precedence over fairness and Full.
In NetworkLayer, the first such APDU ends dispatch; the first such control disables that stream. Later discarded controls are not admission attempts. Routers keep forwarding and count each closed local-admission attempt. Dropping already queued items with the receiver is not an admission drop.