Mastering Swoole Timer: tick, after, clear and Advanced Methods Explained

Overview

Swoole provides a high‑performance timer component with millisecond precision. It is built on epoll_wait (or kevent / poll / select for asynchronous I/O) and setitimer, using a min‑heap to manage a large number of timers efficiently. The timer API is available from Swoole v4.4.0 onward.

Static Methods

Swoole\Timer::tick()

– alias

swoole_timer_tick()

Swoole\Timer::after()

– alias

swoole_timer_after()

Swoole\Timer::clear()

– alias

swoole_timer_clear()

tick() – Repeating Timer

Description: Creates a periodic timer that fires every $msec milliseconds until it is explicitly cleared with Swoole\Timer::clear().

Signature:

int Swoole\Timer::tick(int $msec, callable $callback, mixed ...$params);

Example:

$timer_id = Swoole\Timer::tick(3000, function (int $timer_id, $param1, $param2) {
    echo "timer_id #{$timer_id}, after 3000ms.
";
    echo "param1 is {$param1}, param2 is {$param2}.
";
    // schedule another tick after 14000ms
    Swoole\Timer::tick(14000, function (int $timer_id) {
        echo "timer_id #{$timer_id}, after 14000ms.
";
    });
}, "A", "B");

after() – One‑Shot Timer

Description: Executes the callback once after the specified delay and then destroys the timer.

Signature:

int Swoole\Timer::after(int $msec, callable $callback, mixed ...$params);

Example:

$str = "Swoole";
Swoole\Timer::after(1000, function () use ($str) {
    echo "Hello, {$str}
";
});

clear() – Remove a Timer

Description: Clears a timer identified by its ID.

Signature: bool Swoole\Timer::clear(int $timer_id); Example:

$timer = Swoole\Timer::after(1000, function () {
    echo "timeout
";
});
var_dump(Swoole\Timer::clear($timer)); // bool(true)

Additional Utility Methods

Swoole\Timer::clearAll()

– clears all timers in the current worker process. Swoole\Timer::info(int $id) – returns an associative array with information about the specified timer. Swoole\Timer::list() – returns an iterator that can be used to traverse all timer IDs. Swoole\Timer::stats() – provides overall timer statistics as an array. Swoole\Timer::set(array $settings) – configures timer parameters; for example, disabling coroutine support with ['enable_coroutine' => false].

Usage Context

In synchronous I/O processes (e.g., Manager and TaskWorker), timers are implemented with setitimer and signals. In asynchronous I/O processes, the timeout mechanisms of epoll_wait, kevent, poll or select are used.

The code snippets above demonstrate how to create periodic and one‑shot timers, pass additional parameters, and cancel timers, providing a practical reference for integrating high‑precision timers into Swoole‑based PHP applications.