Struct PriorityFanout 

pub struct PriorityFanout { /* private fields */ }

Implementations

impl PriorityFanout

pub const PAYLOAD_BYTES: usize = PAYLOAD_BYTES

pub fn create( base_path: impl AsRef<Path>, n_priorities: usize, ring_capacity: usize, ) -> Result<Self, FanoutError>

Create a fanout with n_priorities levels (0..n; 0 = lowest, n-1 = highest), each ring sized to ring_capacity slots. All rings have the same capacity; configure based on the expected burst per priority.

pub fn open( base_path: impl AsRef<Path>, n_priorities: usize, ring_capacity: usize, ) -> Result<Self, FanoutError>

Open an existing fanout. Pass the SAME n_priorities and ring_capacity the creator used.

pub fn n_priorities(&self) -> usize

pub fn submit(&self, priority: usize, payload: &[u8]) -> Result<(), FanoutError>

Submit a payload at the given priority level. priority must be in 0..n_priorities. Returns Err(Ring(Full)) when that priority’s ring is full.

pub fn try_drain_highest(&self, out: &mut [u8]) -> Result<usize, FanoutError>

Drain ONE item from the highest non-empty priority. Returns the priority of the item that was drained. Returns Err(Empty) only when ALL rings are empty.

pub fn try_drain_priority( &self, priority: usize, out: &mut [u8], ) -> Result<(), FanoutError>

Drain ONE item from a specific priority. Returns Err(Ring(Empty)) when that ring is empty. Useful for dedicated workers that only handle a specific class.

pub fn active_priorities(&self) -> u64

Snapshot the current active-priority bitmap.

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

Highest currently-active priority (None when all empty).

pub fn approx_pending(&self, priority: usize) -> Option<usize>

Approximate pending count for a specific priority (each ring’s own approx_len).

pub fn approx_total_pending(&self) -> usize

Approximate total pending across all priorities.

pub fn flush(&self) -> Result<(), FanoutError>

Sync the bitmap and all rings to disk.

pub fn flush_async(&self) -> Result<(), FanoutError>

Non-blocking flush of the bitmap and all rings. Delegates to each inner primitive’s flush_async. Note: Windows is only partially async (sync to page cache, not to disk).

Trait Implementations

impl AdaptiveInstance for PriorityFanout

fn header(&self) -> &HandshakeHeader

fn ring(&self) -> &ObservationRing

fn make_policy(&self) -> Box<dyn Policy>

fn apply_migration(&self, new_tag: u32)

Called by the sidecar when the policy returns a new strategy tag. Default implementation: just set the tag on the header. Primitives that need heavier migration (data-layout swap) override this to perform the swap before (or after) updating the tag.