Struct Budget 

#[non_exhaustive]
pub struct Budget {
    pub max_trials: Option<u64>,
    pub max_fidelity_units: Option<u64>,
    pub deadline_millis: Option<u64>,
}

What a study is allowed to spend.

Every field is optional; None means unbounded. Budgets are enforced at ask time and exposed to objectives through TrialCtx::budget, because an RL run legitimately needs to know how many environment steps it may use (the budget).

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

max_trials: Option<u64>

Maximum number of trials to create.

max_fidelity_units: Option<u64>

Cooperative maximum total fidelity, in the study’s ResourceUnit, summed over durable trial reports.

The gate is evaluated from a storage snapshot before new work starts. Already-running trials may therefore carry the durable total past this value when multiple handles execute concurrently. Use it as a stop signal, not as an atomic cross-process reservation.

The overshoot is bounded, not unknown. Admission stops the instant the durable total reaches the limit, so everything above it is work that was already in flight: with at most P trials in flight at once, across all handles and each handle’s parallelism workers, and a per-trial charge of at most F units, the total can exceed the limit by at most P * F. A handle running one trial at a time, alone, therefore overshoots by at most the one trial that crossed the line.

A hard atomic reservation was considered and deliberately not built: it would need an owning cross-process protocol to reserve and settle units before every evaluation, and this budget stops a search rather than metering a paid resource, so the bound above is what the contract owes.

deadline_millis: Option<u64>

Wall-clock deadline, in the study clock’s milliseconds. Compared against a Clock; never read from the OS here.

Implementations

impl Budget

pub const fn new() -> Self

An unbounded budget.

pub const fn new_with_trials(max_trials: u64) -> Self

A budget of max_trials trials.

pub const fn with_fidelity_units(self, units: u64) -> Self

Sets the cooperative fidelity budget.

This is an ask-time stop signal based on durable reports, not an atomic reservation. Concurrent in-flight trials can overshoot it.

pub const fn with_deadline_millis(self, millis: u64) -> Self

Sets the deadline, in the study clock’s milliseconds.

pub const fn is_unbounded(&self) -> bool

true if nothing is limited.

pub fn is_exhausted( &self, trials: u64, fidelity_units: u64, now_millis: u64, ) -> bool

true if the budget is exhausted at (trials, fidelity_units, now).

now_millis comes from the study’s Clock.

Trait Implementations

impl Clone for Budget

fn clone(&self) -> Budget

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Budget

impl Debug for Budget

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

Formats the value using the given formatter.

impl Default for Budget

fn default() -> Budget

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Budget

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for Budget

impl PartialEq for Budget

fn eq(&self, other: &Budget) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for Budget

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Budget