使用PHP函数进行网站性能监控和优化的代码示例

$start = microtime(true);
 
// 网站代码
 
$end = microtime(true);
$executionTime = $end - $start;
 
echo "脚本执行时间：{$executionTime} 秒";

$memoryUsage = memory_get_usage();
$peakMemoryUsage = memory_get_peak_usage();
 
echo "脚本内存使用情况：{$memoryUsage} 字节";
echo "脚本峰值内存使用量：{$peakMemoryUsage} 字节";

$qcEnabled = (bool) ini_get('mysqlnd_qc.enabled');
$qcHitRatio = $qcEnabled ? (double) ini_get('mysqlnd_qc.cache_hit_ratio') : 0.0;
 
echo "缓存是否开启：{$qcEnabled}";
echo "缓存命中率：{$qcHitRatio}";

function getCachedData($key, $expiration = 3600)
{
    $data = apc_fetch($key);
 
    if ($data === false) {
        // 从数据库或其他数据源获取数据
        $data = fetchDataFromDatabase();
 
        // 将数据存入缓存
        apc_store($key, $data, $expiration);
    }
 
    return $data;
}

$ch = curl_init();
$url = 'http://www.example.com';
 
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HEADER, false);
curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 5);
 
$start = microtime(true);
 
$response = curl_exec($ch);
 
$end = microtime(true);
$executionTime = $end - $start;
 
echo "HTTP请求响应时间：{$executionTime} 秒";
 
curl_close($ch);