Struct Metrics 

pub struct Metrics { /* private fields */ }

Lock-free counters for BEAM actor sends and drops.

Cheap to clone via Arc<Metrics>. Designed to be passed via ActorContext (Composition-Root IoC) so any actor can record metrics without coupling to a global registry.

All counters are cumulative for the lifetime of the Metrics instance. They never reset — start a new Metrics if you need per-window observation.

Counter semantics

• dropped_sends: incremented when Addr::send returns Err(()) in a fire-and-forget context. This is the primary “silent drop is no longer invisible” counter.
• reaped_quorums: incremented when the quorum reaper evicts an expired entry. Indicates that quorum timeouts are happening.
• put_acks_seen: incremented when a Node receives any Put ack.
• put_acks_quorum: incremented when a Put ack completes a quorum (the __quorum_met__ sentinel fired).

Implementations

impl Metrics

pub fn new() -> Self

Create a new Metrics with all counters at zero.

pub fn record_dropped_send(&self)

Record that a fire-and-forget send was dropped.

Call this when Addr::send(msg) returns Err(()) in a context where you accept the loss but want to know it happened.

pub fn record_reaped_quorum(&self)

Record that the quorum reaper evicted an expired entry.

pub fn record_put_ack(&self)

Record that a Put ack was received.

pub fn record_quorum_ack(&self)

Record that a Put ack completed a quorum.

pub fn snapshot(&self) -> MetricsSnapshot

Read all counters as a plain struct.

Non-atomic across counters — values may be slightly inconsistent. Acceptable for telemetry; do not use for control flow.

Trait Implementations

impl Debug for Metrics

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

Formats the value using the given formatter.

impl Default for Metrics

fn default() -> Metrics

Returns the “default value” for a type.