发邮件时候遇到的一个问题

 发邮件的程序比较简单，在网上一搜一堆。我用的是自己架的postfix，基本都是默认配置，只改了发送权限的机器跟一些发送重试机制的参数。
但是在真正发邮件的时候，却遇到了一个令我比较郁闷的问题。找了几天也没有找到答案。我用的是Net::Smtp模块发送的，起初我怀疑是没有用好。之后又怀疑一次的tcp连接太多等等，总之，问题没有解决。
无奈之下，我到postfix官网上找到了 Kyle Dent的联系方式。 （之前熟悉postfix也是看他写得那本书）

我去信请教的大概内容：
Hi kdent,
  I get some puzzled problem when i use PostFix.
 
  My program snatched some email list( About 30,000). Then i use my Postfix to send email.
  You know,to reduce connection times,I ONLY set up ONEC time connection to Postfix.
  That is to say,I did it as following step:
 
 
  1) connect the PostFix.
  2) call the mail function in loop.
  3) quit the connect.
 
   
  After ran the program(The program spent 20s or so),i check the postfix log (/var/log/maillog/) ,Only about 1,000 lists have been sent.
  Remainder lists didn't been recorded any info.
 
  Do I need some special config for this aim?
 
  BTW,My postconf is :
。。。


两天之后，kyle给我了答复：
You should take a look at the smtpd limit configuration parameters. They
are all named starting with smtpd and end in limit (smtpd_*_limit). No
doubt you're running into one of those. Also Postfix will report to your
client the reason for not accepting a message. Be sure to check the
response from Postfix to see if a message was accepted or not. If not
then check the error message for the reason.


按图索骥，我又找了一下postfix的配置 ，最终将问题定位在 smptd_recipient_limit 这个参数上。其默认值是1000。

我的代码：
sug smail {
###(1)$smtp = Net::SMTP->new('xx.xx.xx.xx');
$smtp->mail('[email protected]');
$smtp->to('[email protected]');
$smtp->data();
$smtp->datasend('From: [email protected]');
$smtp->datasend("/n");
$smtp->datasend('To: [email protected]');
$smtp->datasend("/n");
$smtp->datasend('Content-type:text/html;Charset=gb2312');
$smtp->datasend("/n");
$smtp->datasend("Subject: test！");
$smtp->datasend("/n/n");
$smtp->datasend("how are you！/n");
$smtp->dataend();
$smtp->dataend();
###(2) $smtp->quit;
}
如此一来，只要将smptd_recipient_limit 调大，把注释1，2放到发送邮件的外部，就可以只建立一次NET socket，然后不停的发送邮件了。

当然去掉注释1,2其逻辑就是每发一封邮件，就new一个Net::SMTP。两种方案，根据实际情况选吧。