On 22.1.2010, at 23.14, Frank Cusack wrote:
This is more or less what dbox's single instance storage is going to do. Maybe in half a year or so.. And you don't even need filesystem deduplication feature. :)
But if the mail system has to handle it, it only knows about mails written at the same time. For example, if postfix delivers mail with a single recipient per mail (the recommended config somewhere, not sure if recommended by postfix or by dovecot), dbox won't get the opportunity to dedup.
Well, doing the multiple-recipients-at-a-time already works with v1.1+ with Maildir.
And for mails which are re-forwarded (pretty common occurrence), again dbox won't get the chance to dedup.
Or will there be a global index?
Yes. That's what dbox SIS is about. You have a global repository of (large) MIME parts, indexed by their SHA1 sum (or something).