title: Sending emails through PHP mail is slow
body: <p>I have a large board with 1 million+ members and I'm experiencing great lag between the sending of emails to each member. At the current rate it would literally take me 3 months to send emails to all 1 million members. </p>
  
  <p>My machine (dedicated):</p>
  
  <ul>
  <li>dual quad xeon</li>
  <li>32 gigs of ram</li>
  <li>Centos 5.4</li>
  <li>vBulletin</li>
  </ul>
  
  <p>I've tried configuring it a number of ways and it is still slow.</p>
  
  <p>The resolution is done locally, so I don't think that's the issue. Any suggestions?</p>
  
  <hr>
  
  <p>vBulletin shows as it sends out the emails (500 at a time) so I know the script isn't timing out or a memory issue. To complete a page of 500, it takes 10 minutes. I am using PHP's <code>mail()</code> function, which is the only other option I have other than SMTP. With previous servers I have not configured myself, it had always been fast. Now trying it with <code>sendmail</code> (PHP's mail function) it is so slow.</p>