On 10 Feb 96 at 18:47, John Debruyn wrote:
> I am working with a new set of lists where they may evolve into several
> thousand subscribers. I would like to know how large (long) a list is
> currently being supported by Majordomo. The Webcom site which got out
> of the server business was unable to maintain a list that got up to about
> 2,000 subscribers. I am hoping that was an abberation.
This conversation perhaps should move to "majordomo-users", although
the performance issues overlap with other list mgmt software.
The maximum size of a Majordomo list depends on machine load. That
comes from two factors: how much work it is for Majordomo to add and
remove people from the list, and how much work it is for your mail
transport to deliver the messages.
In all the cases I've heard discussed, the first part (subscriptions)
aren't usually the problem; it's usually delivery that's the problem.
Majordomo doesn't actually deliver messages; sendmail (or whatever
you have for a mailer) does. So the performance issues for
Majordomo lists are the same for manually-administered lists or any
that depend on the system mailer.
There are a number of ways to deal with this:
- Go to a daily digest. One message a day instead of dozens.
- Get the latest sendmail. Connection caching and related new
features help performance.
- Sort your list by domain. This can help take advantage of any
optimizations in the mailer.
- Queue your messages instead of delivering immediately. It may not
speed up delivery, but it helps system load.
- Break your list into smaller chunks which can be processed
independently. I know of some large lists that are administered by
hand because of the need to split them, but there are a number of
things you can do to automate it. (ObSendmail: "smail" can set a
maximum number of addresses per message; I can't find a corresponding
setting in sendmail. Anyone know?)
- Use bulk_mailer. It splits the list into chunks and sorts by
- Use more than one machine. I run Majordomo proper one one machine
and do actual delivery on another. Some people split their lists
across multiple delivery machines.
All that having been said, I don't have any 2000-member lists myself.
Anyone else care to comment on actual use?
Alan Millar amillar@bolis.SF-Bay.org
System Administrator http://www.bolis.com
Batteries not included.