Struct ScalingPressure 

pub struct ScalingPressure { /* private fields */ }

Available on crate feature scaling only.

Lock-free scaling pressure calculator.

Produces a 0.0-100.0 composite metric for KEDA (or any autoscaler) based on weighted application signals with two hard gates.

All updates are lock-free (Relaxed ordering) – safe to call from any thread without contention.

Example

use hyperi_rustlib::scaling::{ScalingPressure, ScalingPressureConfig, ScalingComponent};

let pressure = ScalingPressure::new(
    ScalingPressureConfig::default(),
    vec![
        ScalingComponent::new("kafka_lag", 0.50, 100_000.0),
        ScalingComponent::new("memory", 0.50, 1.0),
    ],
);

pressure.set_component("kafka_lag", 50_000.0);
pressure.set_memory(400_000_000, 1_000_000_000);

let value = pressure.calculate();
assert!(value > 0.0 && value < 100.0);

Implementations

impl ScalingPressure

pub fn new( config: ScalingPressureConfig, components: Vec<ScalingComponent>, ) -> Self

Create a new scaling pressure calculator.

Components define the weighted signals. Their order doesn’t matter.

pub fn set_component(&self, name: &str, value: f64)

Set a component’s current value (lock-free).

If name doesn’t match any registered component, this is a no-op.

pub fn set_circuit_open(&self, open: bool)

Signal whether the circuit breaker is open.

When open, calculate() returns 0.0 (scaling won’t help when the downstream sink is unavailable).

pub fn set_memory(&self, used_bytes: u64, limit_bytes: u64)

Update memory usage for the memory gate.

When used_bytes / limit_bytes >= memory_gate_threshold, calculate() returns 100.0 to trigger immediate scale-up.

pub fn calculate(&self) -> f64

Calculate composite scaling pressure (0.0-100.0).

Gate logic:

1. Disabled → 0.0
2. Circuit breaker open → 0.0
3. Memory pressure ≥ threshold → 100.0
4. Otherwise → weighted composite capped at 100.0

pub fn snapshot(&self) -> PressureSnapshot

Diagnostic snapshot with per-component breakdown.

pub fn is_enabled(&self) -> bool

Whether the engine is enabled.