Enum WaitStrategy 

pub enum WaitStrategy {
    BusySpin,
    YieldSpin,
    BackoffSpin,
    Adaptive {
        spin_iters: u32,
        yield_iters: u32,
    },
}

Wait strategy for blocking recv() on shared-memory subscriptions.

Controls how the subscriber waits when no new sample is available. The spin/yield phases use platform-specific hints; the OS phase uses futex (Linux), WaitOnAddress (Windows), or WFE (macOS/aarch64).

Variants

BusySpin

Pure busy-spin. No hint instruction. Minimum wakeup latency but consumes 100% of one CPU core. Use on dedicated, pinned cores.

YieldSpin

PAUSE (x86) or SEVL+WFE (aarch64) per iteration. Yields the CPU pipeline to the SMT sibling and reduces power vs BusySpin.

BackoffSpin

Exponential backoff with platform yield hint. Starts with bare spins, then escalates to PAUSE/WFE-based spins with increasing delays. Good for consumers that may be idle for extended periods.

Adaptive

Three-phase: bare spin -> yield -> OS sleep. Default.

Phase 1: bare spin for spin_iters iterations (fastest wakeup). Phase 2: PAUSE/WFE spin for yield_iters iterations. Phase 3: OS-assisted sleep (futex/WaitOnAddress/WFE).

Fields

spin_iters: u32

Bare-spin iterations before yield phase.

yield_iters: u32

Yield iterations before OS sleep phase.

Trait Implementations

impl Clone for WaitStrategy

fn clone(&self) -> WaitStrategy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for WaitStrategy

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

Formats the value using the given formatter.

impl Default for WaitStrategy

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for WaitStrategy

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for WaitStrategy

impl Eq for WaitStrategy

impl StructuralPartialEq for WaitStrategy