Re: slow checking for new mail

[Ken Raeburn <raeburn@cygnus.com>]

Mark Eichin <eichin@cygnus.com> writes:

> is it running movemail once for each nnml group?  I've seen that
> happen to people before, but never understood why...

I think the "<number> g" mechanism was to go through all the groups,
and if the group was at level N or below, fetch new mail.  Which means
with 100 level-N groups, you fetch mail 100 times.

People not using POP wouldn't notice, because it would translate to
(maybe) one movemail invocation, and 99 stat calls that find that the
incoming mail file is zero length; since there's no mail to fetch,
movemail isn't run after the first time.  That optimization can't be
done in the POP case, because you can't see into the mail spool.  If
that optimization were removed, I bet everyone would notice "<number>
g" being slow.

Gnus could remember where it has fetched mail from (movemail source
pathname, or post office reference, or whatever) so far in each pass.
Then it wouldn't need to check the same source twice in one pass.