Aaron Stone wrote:
I don't think we can safely cap message sizes "at a few mb" -- I've certainly sent myself some hefty sized emails and would be quite frustrated if this weren't a possibility because of an intrinsic, hard-coded limit.
I wasn't suggesting capping at a few MB, but rather at something like 128MB.
Yes, it makes the code more complicated, but I think it's only because we still haven't fully adapted our thinking to our model. It occurred to me today that if we were MIME parsing at delivery time, we could also store the mime structure of a message in the database. An IMAP BODY.PEEK for mime structures would be nearly instantaneous. This is probably the single most common request from an email client, especially web-based ones that need to refresh their message list on almost every page hit.
This can be very interesting to do. Of course, we still need to store the message in its original format, but to store some information on mime-parts would be very benificial for performance.
If MySQL can retrieve huge (eg 1 GB) rows easily, and the limitation is only when inserting or updating, then we might be able to use string concatenation to append parts of the message until the body row has the whole thing.
Setting the max_allowed_packet high enough (128MB, maybe even 256MB) would make this unnecessary.
Ilja
