Swoole & OpenSwoole Integration

Swoole and OpenSwoole are event-driven asynchronous and coroutine-based runtimes for PHP that keep workers alive indefinitely in memory.

When using Swoole HTTP servers or task workers, Leakless serves as a defensive shield to audit uncommitted database transactions, drain residual output buffers, monitor Linux kernel RSS drift, and trigger graceful worker reloads before memory leaks cause OS SIGKILL termination.

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Swoole HTTP Server Integration

In a Swoole HTTP server script (e.g. server.php), initialize Leakless in the worker process and instrument the request event callback:

<?php

declare(strict_types=1);

use Swoole\Http\Request;
use Swoole\Http\Response;
use Swoole\Http\Server;
use TheMattos\Leakless\DTOs\Config;
use TheMattos\Leakless\Leakless;

// 1. Create the Swoole Server
$server = new Server('0.0.0.0', 9501);

$config = new Config(
    maxDriftMb: 64,
    consecutiveViolationsThreshold: 5,
    recycleCooldownSeconds: 10,
    checkTransactions: true,
    resettables: [
        App\Services\WorkerMetricsBuffer::class,
    ],
);

/** @var Leakless|null $leakless */
$leakless = null;

// 2. Initialize Leakless when each worker process starts (WorkerStart)
$server->on('WorkerStart', function (Server $server, int $workerId) use ($config, &$leakless) {
    $leakless = new Leakless($config);
    $leakless->captureBaselineMetrics();
});

// 3. Handle incoming HTTP requests
$server->on('request', function (Request $request, Response $response) use ($server, &$leakless) {
    $leakless?->startRequest();

    try {
        // Dispatch to your application logic
        $response->header('Content-Type', 'application/json');
        $response->end(json_encode(['status' => 'success']));
    } finally {
        // 4. Audit transactions, drain buffers, and assess memory drift
        $report = $leakless?->endRequest();

        // 5. Gracefully restart worker when thresholds are breached
        if ($report !== null && $report->shouldRecycle) {
            $server->reload();
        }
    }
});

$server->start();

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Important Considerations for Coroutines

When running with Swoole coroutines (enable_coroutine = true), keep in mind:

• Per-Request State: Do not store request-scoped data (such as authenticated user credentials or request bodies) in global static properties, because multiple coroutines executing concurrently within the same worker would access the same global memory space. Use Swoole\Coroutine::getContext() or framework-level contextual containers.
• Worker-Level Resources: Leakless resettables, StateRollback, and TransactionGuard protect worker-level pools, global environment flags (timezone, error_reporting), and prevent physical memory exhaustion.