Sending PHP mails asynchronously

If using sendmail as transport agent, setting the "DeliveryMode" to "background" (asynchronous) instead of the default "interactive" (synchronous) makes mail() a lot faster, while still sending immediately.



You can either use the "additional parameters", e.g. mail($to, $subject, $message, $headers, 'O DeliveryMode=b'), or make this mode default by changing php.ini's "sendmail_path" to 'sendmail -t -i -O DeliveryMode=b'.