Struct TimerWheel 

pub struct TimerWheel { /* private fields */ }

Timer wheel for managing scheduled timers.

The timer wheel stores active timers indexed by ID and checks for expired timers during each tick. Expired timers have their callbacks scheduled as tasks on the work queue.

Thread Safety

The wheel uses a Mutex<HashMap> internally, making it safe to schedule and cancel from multiple threads.

Implementations

impl TimerWheel

pub fn new() -> Self

Create a new timer wheel with default capacity.

pub fn with_max_timers(max_timers: usize) -> Self

Create a timer wheel with specified maximum timer count.

pub fn schedule_oneshot<F>( self: &Arc<Self>, delay: Duration, priority: Priority, work: F, ) -> TimerHandle

where F: FnOnce() + Send + 'static,

Schedule a one-shot timer.

Returns a handle that cancels the timer when dropped.

pub fn schedule_periodic<F>( self: &Arc<Self>, interval: Duration, priority: Priority, work: F, ) -> TimerHandle

where F: Fn() + Send + Sync + 'static,

Schedule a periodic timer.

Returns a handle that cancels the timer when dropped.

pub fn cancel(&self, id: TimerId) -> bool

Cancel a timer by ID.

Returns true if the timer was found and cancelled, false if it was already cancelled or has fired.

pub fn is_pending(&self, id: TimerId) -> bool

Check if a timer is still pending (scheduled but not yet fired).

Returns true if the timer exists and hasn’t been cancelled or fired.

pub fn tick(&self, now: Instant) -> Vec<Task>

Process expired timers and return tasks to execute.

This should be called during each tick with the current time. Returns a vector of tasks for expired timers.

pub fn pending_count(&self) -> usize

Get the number of pending timers.

pub fn dropped_count(&self) -> u64

Get the number of timers dropped due to capacity limits.

Trait Implementations

impl Debug for TimerWheel

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

Formats the value using the given formatter.

impl Default for TimerWheel

fn default() -> Self

Returns the “default value” for a type.