Just an addition to the previous note re: exec('renice...'). The exit_func() will not set the priority back to normal (0) (at least on linux), unless the user that the webserver is running as is a super user (bad idea). You can decrease the priority of the running task, but not increase it again. See man page for renice.
To prevent subsequent requests running at the lower priority I called apache_child_terminate() on shutdown.
proc_nice
(PHP 5)
proc_nice — Change the priority of the current process
Popis
bool proc_nice ( int $increment )proc_nice() changes the priority of the current process by the amount specified in increment. A positive increment will lower the priority of the current process, whereas a negative increment will raise the priority.
proc_nice() is not related to proc_open() and its associated functions in any way.
Seznam parametrů
- increment
The increment value of the priority change.
Návratové hodnoty
Vrací TRUE při úspěchu, FALSE při selhání. If an error occurs, like the user lacks permission to change the priority, an error of level E_WARNING is also generated.
Poznámky
Availability: proc_nice() will only exist if your system has 'nice' capabilities. 'nice' conforms to: SVr4, SVID EXT, AT&T, X/OPEN, BSD 4.3. This means that proc_nice() is not available on Windows.
proc_nice
12-Aug-2004 04:20
10-Nov-2003 02:34
If you don't have PHP5 and needs to nice your process this works good.
<?php
function proc_nice($priority) {
exec("renice +$priority ".getmypid());
}
//You also need a shutdown function if you don't want to leave your http deamons with a modified priority
function exit_func(){
// Restore priority
proc_nice(0);
}
register_shutdown_function('exit_func');
?>
