Well, firstly, you haven't made a very good case for not using something free and extant like Mailman, which is designed explicitly to handle mailing lists, and which will likely scale far better than something hand-rolled.

Secondly, you can group your addresses a bit, sending a message to 20 recipients at a time, and letting the e-mail server sort it out. 

$cnt = 0;
@addr_slice = @addresses[$cnt..$cnt+20];

#Now, when you create your message:
$msg = MIME::Lite->new (
  From => $wai,
  To => join(', ',@addr_slice),
  Subject => $subject,
  Type =>'multipart/mixed'
  ) or die "Error creating multipart container: $!\n";

[download]

But, I would work through a massive refactor of your code. It isn't fault-tolerant, there are a number of issues that would be caught by -w and use strict, and it demonstrates a lack of understanding of how mail systems and distribution lists work. I'm not being insulting, BTW: just suggesting that understanding more about how mail works would help improve your code.

Better than a refactor -- use a tool that's already designed for this task, like Mailman.

Anima Legato
.oO all things connect through the motion of the mind

In reply to Re: Most efficient way to send mass email? by legato
in thread Most efficient way to send mass email? by JaredHess

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