PHP爬虫之百万级别知乎用户数据爬取与分析(4)

<?php public static function getInstance() { static $instances = array(); $key = getmypid();//获取当前进程ID if ($empty($instances[$key])) { $inctances[$key] = new self(); } return $instances[$key]; }

11、PHP统计脚本执行时间

因为想知道每个进程花费的时间是多少，因此写个函数统计脚本执行时间：

function microtime_float() { list($u_sec, $sec) = explode(' ', microtime()); return (floatval($u_sec) + floatval($sec)); } $start_time = microtime_float(); //do something usleep(100); $end_time = microtime_float(); $total_time = $end_time - $start_time; $time_cost = sprintf("%.10f", $total_time); echo "program cost total " . $time_cost . "s\n";