Struct RuntimeConfig 

pub struct RuntimeConfig {
    pub thread_count: Option<usize>,
    pub jit_threshold: Option<u32>,
    pub signal_delivery: SignalDeliveryConfig,
    pub completion_retry: CompletionRetryConfig,
    pub outbox_enabled: bool,
}

Configuration used when constructing the embedded BEAM runtime.

Fields

thread_count: Option<usize>

Optional scheduler thread count supplied by the engine builder.

None is passed through to beamr so the embedded runtime applies its own runtime-aware default.

jit_threshold: Option<u32>

Optional JIT compilation threshold supplied by the engine builder.

None is passed through to beamr so the embedded runtime applies its own default (beamr::jit::profiler::DEFAULT_JIT_THRESHOLD, 1000 recorded calls per (module, function, arity) at the version this builds against). Nothing here invents a value.

Why this is reachable at all

beamr counts calls per MFA and compiles once the count reaches the threshold. Until this field existed the engine held the scheduler and never named the threshold, so the compile point was unreachable from aion — there was no way to move the moment of compilation, and therefore no way to test whether a fault tracks it.

That is what this is for: a proportionality instrument. Halving the threshold should halve the call count at which a compile-correlated fault appears, which predicts a number rather than explaining one. A fault that moves with the threshold is caused by compilation; a fault that does not is not, however well the arithmetic happened to fit.

🔴 What a large value does, and what it does NOT do

This is not a JIT off-switch, and must not be documented as one. beamr::jit::profiler::JitProfiler::record_call increments with saturating_add(1) and then compiles unless new_count < threshold (jit/profiler.rs:253-262). At u32::MAX the counter saturates at u32::MAX and the comparison stops being true, so the MFA compiles — after 4,294,967,295 recorded calls to that one MFA.

Both halves of that sentence are load-bearing. It is a real horizon, not a semantic quibble: at the ~5 calls per durable wait measured on this engine that is ~859 million waits, so a large value genuinely defers compilation past any workload this engine will run. And it is genuinely not “off”: the compile still happens on the other side of that horizon, so anything relying on it never happening is relying on the workload, not on the configuration. beamr’s own scheduler-level disable is the answer to “off”, and it is a separate beamr release; this field cannot stand in for it.

The threshold is stored in an AtomicU32 read by current_threshold (jit/profiler.rs:109, :189-191). beamr can retune it at runtime via tune_threshold, but only when an embedder drives that call, and aion never does — so a value set here is the value that governs.

signal_delivery: SignalDeliveryConfig

Bounded readiness and retry policy for live signal mailbox delivery.

completion_retry: CompletionRetryConfig

Unbounded backoff ladder for durable completion retries.

outbox_enabled: bool

Whether the durable-outbox fan-out dispatch path is enabled.

Implementations

impl RuntimeConfig

pub fn new(thread_count: Option<usize>) -> Self

Create runtime configuration from the builder-supplied scheduler count.

pub const fn with_jit_threshold(self, jit_threshold: Option<u32>) -> Self

Override the JIT compilation threshold passed to beamr’s scheduler.

Read Self::jit_threshold before using this. In particular a large value defers compilation past any realistic workload but does not disable the JIT, and must not be described as doing so.

pub const fn with_signal_delivery( self, signal_delivery: SignalDeliveryConfig, ) -> Self

Override the signal delivery retry policy.

pub const fn with_completion_retry( self, completion_retry: CompletionRetryConfig, ) -> Self

Override the durable completion-retry backoff ladder.

pub const fn with_outbox_enabled(self, enabled: bool) -> Self

Override whether the durable-outbox fan-out dispatch path is enabled.

Trait Implementations

impl Clone for RuntimeConfig

fn clone(&self) -> RuntimeConfig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for RuntimeConfig

impl Debug for RuntimeConfig

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

Formats the value using the given formatter.

impl Default for RuntimeConfig

fn default() -> RuntimeConfig

Returns the “default value” for a type.

impl Eq for RuntimeConfig

impl PartialEq for RuntimeConfig

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for RuntimeConfig