On Thu, 27 Jan 2005 09:39:32 +0000 (GMT) Philip Hazel <ph10@???> wrote:
> On Wed, 26 Jan 2005, Phil Chambers wrote:
>
> > I am concerned about handling 20,000 users in one go.
>
> So would I be!
>
> > I have set "batch_max = 1000" on the LMTP transport.
> >
> > Will the SMTP transport sending from the list server to the cyrus
> > server time out?
>
> Depends on how fast the cyrus server will accept such a message. You
> can, of course, adjust the timeout on the transport.
>
> > As I understand it, exim normally delivers "on the fly" when a message
> > is received by SMTP for local delivery (LMTP appears to be a local
> > transport). Does batch_max alter that so that the SMTP session closes
> > straight after the DATA phase or does the session wait until all
> > deliveries have completed?
>
> There is no difference at all between what you call "on the fly"
> delivery and a "from the queue" delivery. Your concept of an "on
> the fly" delivery is erroneous, I'm afraid.
>
> For ALL messages that it receives, Exim writes the message to disk,
> checks that it is safely written, then sends the acknowledgement to the
> sender. In other words, the DATA phase ends as soon as the message is
> safely received. (The only exception is if you set the mua_wrapper
> option, which I assume you will not be using in these circumstances.)
>
> If it is to start an "immediate delivery", it then starts up a delivery
> process for that message. If not, it does nothing. In this case a
> delivery process is started at some later time by a queue runner. The
> actual delivery proceeds in an identical manner in both cases.
That is very helpful. It means I need not worry about smtp timing out.
> > Perhaps I need to set queue_only in a data ACL when there is a large
> > number of recipients.
>
> That will make no difference for a single message. It might make a
> difference if there are a lot of similar messages at the same time,
> because it will have the effect of serializing their delivery.
The lists which are this large are restricted, so I have control over when and how
often messages are sent, so I need not be concerned about several such messages
being close together.
Thanks for the prompt and full answer to my question.
Phil.
---------------------------------------
Phil Chambers (postmaster@???)
University of Exeter
