Struct SupervisorConfig 

pub struct SupervisorConfig {
    pub grace: Duration,
    pub max_concurrent: usize,
    pub bus_capacity: usize,
    pub restart: RestartPolicy,
    pub backoff: BackoffPolicy,
    pub timeout: Duration,
}

Global configuration for the supervisor runtime.

Defines:

• Shutdown behavior: grace period for graceful termination
• Concurrency limits: max simultaneous tasks
• Event system: bus capacity for event delivery
• Task defaults: restart policy, backoff strategy, timeout

Field semantics

• grace: Maximum wait for tasks to stop gracefully (0s = no wait, force immediately)
• max_concurrent: Task concurrency limit (0 = unlimited)
• bus_capacity: Event bus ring buffer size (min 1; clamped by Bus)
• timeout: Default per-task timeout (0s = no timeout)
• restart: Default restart policy (can be overridden per-task)
• backoff: Default backoff strategy (can be overridden per-task)

Notes

All fields are public for flexibility. Prefer using helper accessors to avoid sprinkling sentinel checks (0) across the codebase.

Fields

grace: Duration

Maximum time to wait for graceful shutdown before force-terminating.

When a shutdown signal is received:

• Tasks are cancelled via CancellationToken
• Supervisor waits up to grace for tasks to exit
• If timeout exceeds, returns RuntimeError::GraceExceeded

max_concurrent: usize

Maximum number of tasks to run concurrently.

• 0 = unlimited (no semaphore)
• n > 0 = at most n tasks run simultaneously

Applied globally across all tasks in the supervisor.

bus_capacity: usize

Capacity of the event bus broadcast channel ring buffer.

Slow subscribers that lag behind more than bus_capacity messages will receive Lagged and skip older items. Minimum value is 1 (enforced by Bus).

restart: RestartPolicy

Default restart policy for tasks.

Used by TaskSpec::with_defaults(). Can be overridden per-task.

backoff: BackoffPolicy

Default backoff policy for retries.

Used by TaskSpec::with_defaults(). Can be overridden per-task.

timeout: Duration

Default task timeout.

• Duration::ZERO = no timeout (task runs until completion)
• > 0 = timeout applied per task attempt

Used by TaskSpec::with_defaults(). Can be overridden per-task.

Implementations

impl SupervisorConfig

pub fn concurrency_limit(&self) -> Option<usize>

Returns the global concurrency limit as an Option.

• None → unlimited (no semaphore)
• Some(n) → at most n concurrent tasks

pub fn default_timeout(&self) -> Option<Duration>

Returns the default per-task timeout as an Option.

• None → no timeout
• Some(d) → timeout applied per attempt

pub fn bus_capacity_clamped(&self) -> usize

Returns a bus capacity clamped to a minimum of 1.

The Bus should use this value to avoid constructing an invalid channel.

Trait Implementations

impl Clone for SupervisorConfig

fn clone(&self) -> SupervisorConfig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SupervisorConfig

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

Formats the value using the given formatter.

impl Default for SupervisorConfig

fn default() -> Self

Default configuration:

• grace = 60s (reasonable graceful shutdown window)
• max_concurrent = 0 (unlimited)
• bus_capacity = 1024 (good baseline)
• timeout = 0s (no timeout)
• restart = RestartPolicy::OnFailure (restart on errors only)
• backoff = BackoffPolicy::default() (exponential backoff)