Timo Sirainen wrote:
On Wed, 2009-08-12 at 11:35 -0700, Daniel L. Miller wrote:
Timo Sirainen wrote:
Also the mime structure could be torn apart to store
attachments individually - the motivation being single instance storage
of large attachments with identical content... Anyway, these seem like
very speculative directions...
Yes, this is also something in dbox's far future plans.
Speaking as a pathetic little admin of a small site of 20 users, my
needs for replication & scalability are quite minor. However,
single-instance storage would be a miracle of biblical proportions. Has
any progress been made on this?
Do you need per-MIME part single instance storage, or would per-email be
enough? Since the per-email can already done with hard links.
Definitely per MIME part.
Do you have a roadmap for how you plan on implementing it?
I've written about it a couple of times I think, but no specific plans.
Something about using hashes anyway.
I don't know if you've considered this at all - this was my first thought:
If you're able to store a message with the attachments separately, then
you can come up with an attachment database (not meaning to imply SQL
backend). Then after breaking the message up into message +
attachments, you scan the attachment database to see if it is already
present prior to saving it. This could mean that not only could we save
on the huge space wasted by idiots merrily forwarding large attachments
to multiple people, but even received mails with embedded graphical
signatures would benefit.
Yes, that's pretty much how I thought about it. It's anyway going to be
dbox-only feature. Would be way too much trouble with other formats.
dbox-only is fine. I could care less about the storage method chosen -
filesystem, db, encrypted, whatever - but I believe the impact on
storage - and possibly indexes & searching - would be huge.
On the personal greedy side, if you want to see a mass corporate
migration to Dovecot, with potential service contracts - that would be a
feature worth talking about. I can see IT manager's eyes light up at
hearing about such a item - and I've never heard of any other mail
server supporting such a thing.
--
Daniel
