Struct MetricsSnapshot 

pub struct MetricsSnapshot { /* private fields */ }

A read-only, point-in-time representation of Metrics.

Created via Metrics::snapshot or [Metrics::into].

Implementations

impl MetricsSnapshot

pub fn hit_count(&self) -> u64

Returns the total number of hits recorded at the time of the snapshot.

pub fn miss_count(&self) -> u64

Returns the total number of misses recorded at the time of the snapshot.

pub fn eviction_count(&self) -> u64

Returns the total number of evictions recorded at the time of the snapshot.

pub fn miss_rate(&self) -> f64

Calculates the miss rate ($misses / (hits + misses)$).

Returns 0.0 if no activity was recorded to prevent division-by-zero errors.

pub fn hit_rate(&self) -> f64

Calculates the hit rate ($hits / (hits + misses)$).

Returns 0.0 if no activity was recorded.

pub fn latency(&self, percentile: LatencyPercentile) -> u64

Returns the latency value at a specific percentile using a type-safe enum.

This is the preferred method for monitoring cache performance, as it explicitly categorizes measurements into median, tail, and extreme tail latencies.

Performance

The lookup is $O(1)$ relative to the number of samples in the histogram.

Trait Implementations

impl Debug for MetricsSnapshot

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

Formats the value using the given formatter.

impl From<&Metrics> for MetricsSnapshot

fn from(metrics: &Metrics) -> Self

Converts to this type from the input type.