Re: [exim] overall rate limiting?

Peter D. Gray wrote:

> as well. It would be nice to set up the
> routing machines so that they process a fixed number of
> email messages per second. This would avoid large load spikes
> on our mail stores as mail floods in.
>
> Any ideas or suggestions?

To even out the load, you can try tweaking these options:


deliver_queue_load_max = 2.00
queue_only_load = 1.50
remote_max_parallel = 16


That will not grant for x mails processed per unit of time, but it helps
to even out the spikes by delaying the processing if needed.

It's probably much better than limiting to handling x mails per unit of
time because it allows the servers to operate at full throttle without
being overwhelmed by the amount of mail to handle, provided that you use
reasonable values adapted to the performance of your servers. If that
doesn't suffice, you will need faster or more servers anyway.


See also:

split_spool_directory = true
check_spool_space = 1024M
smtp_check_spool_space = true

message_size_limit = 100M
bounce_return_size_limit = 8k

queue_run_max
smtp_accept_max


GH