PHP Opcache & JIT Performance Improvement Test And Configuration Verification

opcache-test.php

<?php

$opcacheEnable = $argv[1] ?? $_GET['opcacheEnable'] ?? null;
if($opcacheEnable === null){
    $message = "
        Detected a {{percentImprovement}}% performance improvement from Opcache & JIT (in a basic test case).
        Please run this script several times to ensure cache priming & consistent results.
        Run this script in both the browser and the command line, as configurations could differ between the two.
        If a more than 100% improve is not seen consistently, one of the following php.ini values is likely incorrect (current values shown):
    ";

    $message = rtrim($message, " ");
    
    foreach([
        'opcache.enable',
        'opcache.enable_cli',
        'opcache.jit',
        'opcache.jit_buffer_size',
        'opcache.memory_consumption',
    ] as $name){
        $message .= "            $name = " . ini_get($name) . "\n";
    }

    if(PHP_SAPI === 'cli'){
        $action = function($arg){
            return shell_exec("php -d opcache.enable=$arg " . __FILE__ . " this-value-does-not-matter");
        };

         // Run the action once to prime the cache
        $action(1);

        $enabledTime = $action(1);
        $disabledTime = $action(0);
        $percentImprovement = round(($disabledTime - $enabledTime) / $enabledTime * 100);

        $message = str_replace('{{percentImprovement}}', $percentImprovement, $message);

        echo $message . "\n";
    }
    else{
        // We're in a browser
        ?>
        <script>
            (async () => {
                const performRequest = async (value) => {
                    const response = await fetch('?opcacheEnable=' + value)
                    return await response.text()
                }

                // Ignore first value, since cache may not be populated let
                await performRequest(1)

                const enabledTime = await performRequest(1)
                const disabledTime = await performRequest(0)
                const percentImprovement = Math.round((disabledTime - enabledTime) / enabledTime * 100)
                document.write('<pre>' + <?=json_encode($message)?>.replace('{{percentImprovement}}', percentImprovement).replaceAll("\n", "<br><br>") + "</pre>")
            })()
        </script>
        <?php
    }
}
else{
    if($opcacheEnable === '0'){
        ini_set('opcache.enable', 0);
    }
    
    $start = microtime(true);
    
    $path = sys_get_temp_dir() . '/opcache-test-loop.php';
    $expectedContent = '<?php for($i=0;$i<100000000;$i++){}';
    if(!file_exists($path) || file_get_contents($path) !== $expectedContent){
        file_put_contents($path, $expectedContent);
    }
    
    require $path;
    
    echo microtime(true) - $start;
}