Struct CheckpointBarrierInjector 

pub struct CheckpointBarrierInjector { /* private fields */ }

Cross-thread barrier injector for source operators.

The coordinator thread stores a packed barrier command via trigger. Source operators poll via BarrierPollHandle::poll on each iteration of their event loop.

Fast Path

The poll path is a single AtomicU64::load(Relaxed) — typically < 10ns. Only when a barrier is pending does the source perform a compare-exchange to claim it.

Implementations

impl CheckpointBarrierInjector

pub fn new() -> Self

Create a new injector with no pending barrier.

pub fn handle(&self) -> BarrierPollHandle

Get a handle that source operators use to poll for barriers.

pub fn trigger(&self, checkpoint_id: u64, barrier_flags: u64)

Trigger a new checkpoint barrier.

The next BarrierPollHandle::poll call on any source will observe this barrier and return it. If a previous barrier has not been consumed, it is superseded — this is intentional for the Chandy-Lamport protocol where only the latest checkpoint matters.

Arguments

• checkpoint_id - Unique checkpoint ID (must fit in 32 bits)
• barrier_flags - Barrier flags (must fit in 32 bits)

Panics

Debug-asserts that checkpoint_id and barrier_flags fit in u32.

pub fn epoch(&self) -> u64

Get the current epoch (number of barriers triggered).

Trait Implementations

impl Debug for CheckpointBarrierInjector

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

Formats the value using the given formatter.

impl Default for CheckpointBarrierInjector

fn default() -> Self

Returns the “default value” for a type.