>> Heck, it could be as simple as "each message is 1 directory, >> containing chunks stored one per file, named by integers, and the >> original message is formed by cat'ing the chunks in numerical >> order".
> This turns out to be a pessimization. Of what? One possible goal (not the only consideration) would be for the N copies of a monster attachment received by your N users to occupy space==1 instead of space==N. Cyrus IMAP does this in certain circumstances. Fossil+Venti will do it automatically, but only (at present) if the attachment is aligned the same way in each user's mailbox, which it frequently won't be...or if it's stored out of line in a separate file, which would align it the same way for all N users. Maybe it's not worth worrying about. Dave Eckhardt
