Struct PoolScaler 

pub struct PoolScaler { /* private fields */ }

Pool autoscaler that adjusts min_idle based on pressure signals.

Implementations

impl PoolScaler

pub fn new( policy: ScalingPolicy, initial_min_idle: usize, max_size: usize, ) -> Self

Create a new scaler with the given policy and initial min_idle.

pub fn record_acquire(&mut self, hit: bool)

Record an acquire event. hit = true if served from pool.

pub fn current_min_idle(&self) -> usize

Get the current dynamic min_idle value.

pub fn update_gateway_pressure(&mut self, pressure: f64)

Update the external Gateway pressure signal.

Pressure is a value from 0.0 (idle) to 1.0 (saturated), derived from Gateway metrics like request rate, queue depth, or latency percentiles.

When Gateway pressure is high, the scaler biases toward scaling up even if the local miss rate is moderate.

pub fn gateway_pressure(&self) -> f64

Get the current Gateway pressure value.

pub fn evaluate(&mut self) -> ScaleDecision

Evaluate pressure and return a scaling decision.

Respects cooldown period between decisions.