Struct MultiLevelQueue 

pub struct MultiLevelQueue<T> { /* private fields */ }

Thread-safe multi-level priority queue with anti-starvation aging.

Items are held in five internal VecDeque buckets — one per Priority level. Before every pop call, an aging pass scans lower-priority buckets and promotes items whose wait time exceeds the configured threshold.

Implementations

impl<T> MultiLevelQueue<T>

pub fn new(config: AgingConfig) -> Self

Create a new queue with the given AgingConfig.

pub fn push(&self, item: T, priority: Priority)

Enqueue item at the given priority.

This is a non-async, non-blocking call (only acquires the internal Mutex).

pub fn pop(&self) -> Option<T>

Dequeue the highest-priority available item.

Runs an aging pass before selecting the item, so a previously low-priority item that has waited long enough may be returned ahead of a recently-added same-level item.

Returns None when all buckets are empty.

pub fn len(&self) -> usize

Total number of items across all buckets.

pub fn is_empty(&self) -> bool

Returns true when all buckets are empty.

pub fn len_by_priority(&self) -> [usize; 5]

Per-priority item counts. Index i corresponds to Priority level i.

pub fn stats(&self) -> QueueStats

Snapshot of queue statistics.