Struct WorkerPoolConfig 

pub struct WorkerPoolConfig {
    pub min_threads: usize,
    pub max_threads: usize,
    pub grow_below: f64,
    pub shrink_above: f64,
    pub emergency_above: f64,
    pub memory_pressure_cap: f64,
    pub scale_interval_secs: u64,
    pub async_concurrency: usize,
    pub health_saturation_timeout_secs: u64,
}

Available on crate features worker-batch or worker-pool or worker only.

Configuration for the adaptive worker pool.

All values are overridable via the 8-layer config cascade (CLI > ENV > .env > settings.{env}.yaml > settings.yaml > defaults > rustlib > hard-coded).

Every field is also emitted as a gauge metric for Grafana overlay.

Fields

min_threads: usize

Minimum active worker threads (floor for scaling).

max_threads: usize

Maximum worker threads. 0 = auto-detect from cgroup / available_parallelism.

grow_below: f64

CPU utilisation below this threshold triggers thread growth.

shrink_above: f64

CPU utilisation above this threshold triggers gentle thread reduction.

emergency_above: f64

CPU utilisation above this threshold triggers aggressive thread reduction.

memory_pressure_cap: f64

Memory pressure above this threshold hard-caps threads at min_threads.

scale_interval_secs: u64

How often to re-evaluate scaling (seconds).

async_concurrency: usize

Maximum concurrent async fan-out tasks.

health_saturation_timeout_secs: u64

Seconds the pool must be saturated before reporting unhealthy.

Implementations

impl WorkerPoolConfig

pub fn from_cascade(key: &str) -> Result<Self, ConfigError>

Load config from the cascade under the given key (e.g. “worker_pool”).

Falls back to defaults if the config cascade is not initialised or the key is absent. Validates after loading.

Errors

Returns an error if validation fails (e.g. thresholds out of order).

pub fn validate(&self) -> Result<(), ConfigError>

Validate configuration invariants.

Errors

Returns an error if thresholds are out of order or min > max.

pub fn resolve_max_threads(&mut self)

Resolve max_threads to the effective CPU count.

• max_threads = 0 → auto-detect from available_parallelism (cgroup-aware)
• max_threads > 0 → cap at min(configured, available_parallelism) to avoid creating more threads than physical cores

Trait Implementations

impl Clone for WorkerPoolConfig

fn clone(&self) -> WorkerPoolConfig

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WorkerPoolConfig

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

Formats the value using the given formatter.

impl Default for WorkerPoolConfig

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for WorkerPoolConfig

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for WorkerPoolConfig

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.