Struct ProbationAdmission 

pub struct ProbationAdmission {
    pub freq: Arc<dyn FrequencyEstimator>,
    pub promotion_threshold: u32,
}

Admits a first-ever miss into Probation; once the shared estimator has seen promotion_threshold prior sightings of a hash, admits straight to Main. Reads estimate only — never calls observe (see the ordering invariant in the module docs: a request must never count as evidence for its own promotion).

The estimate read takes one sketch shard, so a fill decision and a concurrent serve completion collide only when their hashes share a shard.

Fields

freq: Arc<dyn FrequencyEstimator>

The shared frequency estimator; read, never written, by this policy.

promotion_threshold: u32

Prior sightings a hash needs before a miss is admitted straight to Segment::Main instead of Probation.

Trait Implementations

impl AdmissionPolicy for ProbationAdmission

fn admit(&self, ctx: &AdmissionContext) -> AdmissionDecision

Judge one miss. Called on the serve path, so it must not block.

impl Debug for ProbationAdmission

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

Formats the value using the given formatter.