When you sleep () a page, you have to wait for all page visits to the entire site. What's going on with this problem?

this problem occurs when using phpstudy, testing under window, session_write_close has no effect, and no specific solution has been found on the Internet.

Feb.28,2021

if you are using session, session_write_close (); open session_start ();

where blocking is needed.
session_write_close();
sleep(10);
session_start();

in this way, you can block normally when you visit the current page, and request normally when you visit other pages, so that other pages cannot be accessed normally because the current blocked page takes up session resources.

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