At 06:37 PM 2/11/99 +0800, Marlon Anthony Abao wrote:
>hello,
>
> with the release of the new linux kernel, the limit of concurrent
>processes is now raised. according to conf-spawn we cannot raise the qmail
>concurrency limit past 256. is there any reason for this?
>
> i know raising this limit would break some unix boxes. is there a
>theoretical reason to limit it just to 256? a heavily built linux box with
>more than ample memory, processing power, and bandwidth with no load except
>mail deliveries would benefit by raising this limit to something even
>higher than 256.
>
> during a recent changeover of mail servers, my linux box was comfortably
>serving a continuous 240 concurrent remote connections over a period of 2
>days.
The short answer is that a single instance of qmail does not support a
concurrency of more than 255. The author acknowledges this limit in TODO.
The long answer is that there is nothing stopping you from having multiple
instances of qmail each with a concurrency limit of 255. /var/qmail1,
/var/qmail2, /var/qmail3, etc.
The only trick is arranging for your mail to be injected into all the queues
you run. I've done this with a randomized sendmail and qmail-inject wrapper.
I'm sure others will suggest equally good ways of using multiple instances.
Regards.
