[pfx] Re: qmgr stalls when default_destination_rate_delay drops below 1s on a node, with a backed-up queue

Yoda via Postfix-users:
>   Our updated tuning rules:                                                                                            
>                                                                   
>     - Minimum rate_delay is 1s. Sub-second is architecturally                                                          
>       impossible at the rate_delay knob, full stop.               
>     - Always set time values at default_destination_* (qmgr fatals                                                     
It is possible if you can afford to configure multiple delivery transports
that have parallel rate delays.

Below is an old posting.

	Wietse

> > I'm working in an email marketing firm, we send more than 50 millions of
> > emails per month, and use postfix for that, and can't resolve a problem
> > with transport for gmail,  in destination_rate_delay, only
> > accepts integers,  why can not use a float?
> 
> The rate delay feature was implemented for end users with an ISP
> that allows only a limited volume of outbound email (less than
> 3600/hour). It turned out to also help for sending mail to providers
> such as Hotmail with very low rate limits.
> 
> The rate delay implementation does not work well for bulk mail,
> because it limits the concurrency to only one delivery at a time.
> So the proper fix is not changing ints to float, but allowing more
> than one delivery at a time.

However, you can increase concurrency by using multiple SMTP
transports and random selection.

In /etc/postfix/master.cf:

    smtp1      unix  -       -       n       -       -       smtp
    smtp2      unix  -       -       n       -       -       smtp
    ...
    smtpN      unix  -       -       n       -       -       smtp

    smtp1_destination_concurrency_failed_cohort_limit = 10
    smtp2_destination_concurrency_failed_cohort_limit = 10
    ...
    smtpN_destination_concurrency_failed_cohort_limit = 10

In /etc/postfix/main.cf:

    smtp1_destination_rate_delay = 1
    smtp2_destination_rate_delay = 1
    ...
    smtpN_destination_rate_delay = 1

    transport_maps = 
        inline:{
                { $myhostname = $local_transport }
                { localhost = $local_transport }
                { localhost.$mydomain = $local_transport }
                # Other domains that don't deliver over SMTP...
        }
    randmap:{ smtp1:, smtp2:, ..., smtpN: }

_______________________________________________
Postfix-users mailing list -- [email protected]
To unsubscribe send an email to [email protected]