mail() stability

KemuriSka

Hi,

How stable is the mail function? I am building a mailing list and I was going to code it something like below:

// Grab emails from MySQL db
foreach ($recipient as $to) {
  mail($to,$subject,$message,$headers);
}

There will probably be a lot of people signing up, but could this code handle it?

Thanks
Ste

dalecosp

Don't know enough to answer your question soundly, but mail() is dependent on the server's MTA. If, for some reason the MTA was having trouble (or was shut down), mightn't your script hit a brick wall? I almost always run mail() thus:

$success=mail($to, $subject, $message, $headers);
if (!$success) { echo $error_msg;
exit;
}

KemuriSka

Is there a chance that it will timeout?

RedDragon

you could use

@ini_set('max_execution_time', '1000');
@set_time_limit (1000);

to extend the script execution time to about 10 minutes

Sxooter

If you're sending a couple of notices a day, mail() is a fine way of doing it. If you're sending a few thousand emails a day throughout your company, it's still probably ok.

If you're gonna be processing 100,000 messages or more a night for a mailing list, you might want to run sendmail by hand. Or at least change the default configs in php.ini.

Read up on it a bit with 'man sendmail' and look through all the switches. Especially the -q switch, which tells sendmail to process outgoing mail in big batches instead of one at a time. Telling sendmail to process the mail it's sending every 60 seconds or so will definitely make it much faster at pumping out 100,000+ emails.

Also, look at increasing the size of the spool directory for your outgoing email so it doesn't overflow and lose email.