php - 轮询 Apache 服务器没有响应

Question

当控制消息轮询的脚本正在运行时，我用来开发系统的 apache 服务器将不会响应请求。这仅发生在域级别，这意味着我可以向本地托管的任何其他应用程序发送 http 请求并获得响应。当我最终得到回复时，大约一分钟后。

这是 Js

window.fetch_messages = function ()
{
    var last_message = $("div.message:last").attr('data-ai_id');
    var last_message_status = $("p.message_status:last").text();
    var project_id = getParameterByName('project-id');

    $.ajax({
            url:'/project_messages',
            type:'POST',
            data:{ project_id:project_id, latest_message:last_message, status:last_message_status },
            timeout:50000,
            async: true,
            success:new_messages, // This upon completion also resends the request
            error:function(data){ console.log(data); setTimeout(fetch_messages(),50000); }
    });

}; // When On the page that uses this I call this function to start polling

这是服务器端代码

do 
{
    // Check for status change
    $status_change = $this->mentor_model->query_status($this->project_id, $this->last_message_id, $this->last_message_status, $_SESSION['user']); 

    // Check for new messages
    $messages = $this->mentor_model->query_messages($this->project_id, $this->last_message_id); 

    // If there is a  status update or new message.
    if($messages || $status_change)
    break;

    usleep(1000000);
}
while(empty($messages) && empty($status_change));

echo json_encode(array("messages"=>$messages, "status"=>$status_change));
exit;

运行此操作时，服务器需要很长时间来处理任何请求(无论是 GET、POST 或其他 AJax 请求)。 iv 也尝试过更改这两个代码集，但没有效果，只要其轮询时间较长，服务器将需要很长时间来处理。

我是否有这个错误，或者是否有一些我应该更改的 apache 设置。在 Windows 8.1 上使用 xamp 也尝试了 wamp 没有任何变化

Answer 1

感谢史蒂文。答案直接取自 php 手册页的来源对于 session_write_close();

You can have interesting fun debugging anything with sleep() in it if you have a session still active. For example, a page that makes an ajax request, where the ajax request polls a server-side event (and may not return immediately).

If the ajax function doesn't do session_write_close(), then your outer page will appear to hang, and opening other pages in new tabs will also stall.