A single visitor doesn't just mean a few incidental page requests; it also means an open connection (with a waiting thread) for as long as the visitor stays.

单个的访问不只是意味着一些偶然的页面请求；它还意味着在访问期间有一个持续打开的连接(带有等待线程)。

youdao

One of the primary benefits of RTMP is the connection with the client stays open so it can be used to push data from the server.

RTMP的一个主要好处是可以一直打开与客户端的连接，这样就可以推送服务器端的数据了。

youdao

The connection stays open until it times out and causes the request to get re-initiated.

连接将一直保持开启，直到过期，并导致重新发出请求。

youdao

Unlike other European public transit systems, it stays open 24 hours a day, seven days a week.

BBC: Subway systems by the numbers

But if it stays open its impact will be considerable.

FORBES: Alex Bogusky, On The Next 510 Years In Advertising

If you log into a website and leave Safari, it stays open in the background (unless you explicitly close it or restart the iPhone) and maintains your sessions, but that's the extent of it.

ENGADGET: We've got iPhones, what do you want to know?