Questions about sleep functions

When I used the sleep function, I found that the system is waiting for the localhost to respond when I cannot access the page.

Set_time_limit (0); // the execution time is unlimited. the default php execution time is 30 seconds, so that the program can be executed without limit $ interval = 120; do {$ SQL = "select CPUTotal, UpdateTime from systemcpu where SystemID = $ KeyID"; $ result = mysql_query ($ SQL); $ rows = mysql_fetch_array ($ result ); $ GetTime = (strtotime ($ rows ["UpdateTime"])-8*60*60) * 1000; sleep ($ interval);} while (true );

Reply to discussion (solution)

Do {
........
While (true );

This is an endless loop. of course you have to keep waiting.

Okay, you already know.
I will try to use ajax to implement