This function sets the maximum time in seconds a script is allowed to run before it is terminated. This helps prevent poorly written scripts from tying up the server. The default setting is 30, except when running PHP from the command line, where the default setting is 0.
On non Windows systems, the maximum execution time is not affected by system calls, stream operations etc. Please see the set_time_limit() function for more details.
Your web server can have other timeout configurations that may also interrupt PHP execution. Apache has a Timeout directive and IIS has a CGI timeout function. Both default to 300 seconds. See your web server documentation for specific details.
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