Am 06.07.2010 um 19:12 schrieb Tonix (Antonio Nati): > This is the global value, so keeping it low means to have a few global > connections working. > It would be great if connections could be reused, so only a minimum of > connections should be opened for each destination IP. > > It would be great to have such options: > concurrency remote: as now > new connection threshold [global]: if you have more than xx messages in queue > for single destination IP, open a new connection > max connections limit [global]: per single destination IP max connection limit > new connection threshold [IP]: if you have more than xx messages in queue for > a specific destination IP, open a new connection > max connections limit [IP]: per specific destination IP max connections limit > So, for example, you could put: > for gmail: threshold 300, limit 20 > for yahoo: threshold 500, limit 10 > for myspecific: threshold 0 (infinite), limit 1 > for any: threshold 100, limit 5 > maxconcurrencyremote: 100
Bear with me for a second here: Admittedly, using one connection for multiple transmissions might be more efficient. However, that is only true if you actually have at least n > 1 mails to send to the same domain at a given time. Unless you do emarketing (or have a huge mailing list) you do not know beforehand that this is actually the case. On the contrary, such a situation would be more or less random. This basically means that every time qmail processes an item in its queue, it would need to do something like this: - scan the queue for other emails to the same domain - gather as many as the config says for that domain - open a SMTP connection - transmit the messages. - dequeue the messages The problem is this: For every time you only have one email to a specific domain in the queue, you add overhead instead of reducing it. The queue might be really full and still no other mail in it that needs to be delivered to the same domain. Thus, this makes only sense if you know beforehand that there is a high amount of concurrency to a specific domain. On the other hand: - transmitting one mail per connection is safe. - limits for messages / connection might be subject to change without notice and everyone using such a config would then have lots of bounces, etc. until someone figures out what the ISP in question changed. > I'm just focused on efficient e-mail server, simply. So am I. :-) Martin
