/**
* 创建一个子进程
* @param Worker $worker
* @throws Exception
*/
public function fork_one_task($taskid)
{
$pid = pcntl_fork();
// 主进程记录子进程pid
if ($pid > 0) {
// 暂时没用
self::$taskpids[$taskid] = $pid;
} elseif (0 === $pid) {
log::warn("Fork children task({$taskid}) successful...\n");
self::$time_start = microtime(true);
self::$taskid = $taskid;
self::$taskpid = posix_getpid();
self::$taskmaster = false;
self::$collect_succ = 0;
self::$collect_fail = 0;
while ($this->queue_lsize()) {
// 如果队列中的网页比任务数多，子任务可以采集
if ($this->queue_lsize() > self::$tasknum * 2) {
// 抓取页面
$this->collect_page();
} else {
log::warn("Task(" . self::$taskid . ") waiting...\n");
sleep(1);
}
// 每采集成功一个页面，生成当前进程状态到文件，供主进程使用
$mem = round(memory_get_usage(true) / (1024 * 1024), 2) . "MB";
$use_time = microtime(true) - self::$time_start;
$speed = round((self::$collect_succ + self::$collect_fail) / $use_time, 2) . "/s";
$status = array('id' => self::$taskid, 'pid' => self::$taskpid, 'mem' => $mem, 'collect_succ' => self::$collect_succ, 'collect_fail' => self::$collect_fail, 'speed' => $speed);
util::put_file(PATH_DATA . "/status/" . self::$taskid, json_encode($status));
}
// 这里用0表示正常退出
exit(0);
} else {
log::error("Fork children task({$i}) fail...\n");
exit;
}
}
