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What I've read so far:

  • Postfix Tunning
  • Postfix Bottle Neck Analisys
  • The Book of Postfix (chapter 22)

I have similar specs to this guy but I'm only able to send about ~1300 emails/hour

What I've done:

  • Reduced the time for deferred mails
  • Reduced deferred scans
  • List item
  • Increase maximal backoff time

Some configurations

queue_run_delay = 300s
minimal_backoff_time = 600s
maximal_backoff_time = 3600s
default_process_limit = 100
smtp_connect_timeout = 30s
default_destination_concurrency_limit = 20s
initial_destination_concurrency = 5s
local_destination_concurrency_limit = 2s
virtual_destination_concurrency_limit = 20s

Amavis, clamav, postgrey and spamassasing are also working with postfix and every email is signed by opendkim, the server is used for email marketing and that's why the added services, should I remove them? how much would that affect the reputation of the emails sent?

share|improve this question
The question first is why aren't you getting more throughput (supposing you could). Is the CPU maxed out? Is the disk IO bottlenecking? Is the RAM maxed out? Is your network saturated? Are you sufferring from throttling from Yahoo/AOL/Gmail/etc? Are you just getting bounced? How do you could 1300 emails/hour? – ETL Feb 26 '14 at 3:58
Right now the server’s ram is almost full, that's why I was thinking on removing some services specially clamav since is the one consuming most of the ram – JM Rodriguez Feb 26 '14 at 14:16
default_destination_concurrency_limit - you have it in "seconds", but it is not a time unit. Or is it? – Dalibor Filus Apr 25 at 9:43

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