I'm currently using mbox and mbx with UW-IMAP, mbox for space efficiency and mbx for folders with lots of messages for time efficiency without a large space cost. I've avoided maildir because it has a relatively high space cost; mbox has no inter-message cost while maildir wastes on average half a sector plus an inode for each message. What other formats are there, and has anyone come up with a good format that gives both good time and space characteristics without sacrificing reliability? (I'm aware of the file format list in the UW-IMAP distro: <http://www.washington.edu/imap/documentation/formats.txt.html>)
On Tue, 2004-02-10 at 22:38, Kenneth Porter wrote:> I'm currently using mbox and mbx with UW-IMAP, mbox for space efficiency > and mbx for folders with lots of messages for time efficiency without a > large space cost.The reason why mbx takes more space is that it uses CR+LF linefeeds instead of just LF..> I've avoided maildir because it has a relatively high > space cost; mbox has no inter-message cost while maildir wastes on average > half a sector plus an inode for each message.AFAIK ReiserFS doesn't lose any space (or much).> What other formats are there, and has anyone come up with a good format > that gives both good time and space characteristics without sacrificing > reliability? > > (I'm aware of the file format list in the UW-IMAP distro: > <http://www.washington.edu/imap/documentation/formats.txt.html>)UW-IMAP's author is thinking of some hybrid format where a single mailbox could be built from multiple files, but a single file could contain multiple messages. I think this could be made to work pretty well and reliably. I don't know more about his plans though, I didn't find any discussion about it in c-client list at least. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 189 bytes Desc: This is a digitally signed message part URL: <http://dovecot.org/pipermail/dovecot/attachments/20040225/3df03588/attachment-0001.bin>
--On Wednesday, February 25, 2004 7:43 PM +0200 Timo Sirainen <tss at iki.fi> wrote:> On Tue, 2004-02-10 at 22:38, Kenneth Porter wrote: >> I'm currently using mbox and mbx with UW-IMAP, mbox for space efficiency >> and mbx for folders with lots of messages for time efficiency without a >> large space cost. > > The reason why mbx takes more space is that it uses CR+LF linefeeds > instead of just LF..I was thinking mbox vs maildir. mbx isn't much bigger than mbox, mainly adding the metadata at the front, about 1k per folder.>> I've avoided maildir because it has a relatively high >> space cost; mbox has no inter-message cost while maildir wastes on >> average half a sector plus an inode for each message. > > AFAIK ReiserFS doesn't lose any space (or much).Interesting point. I hadn't considered using ReiserFS for my mail directories. Sounds like a good motivation to try it out.> UW-IMAP's author is thinking of some hybrid format where a single > mailbox could be built from multiple files, but a single file could > contain multiple messages. I think this could be made to work pretty > well and reliably. I don't know more about his plans though, I didn't > find any discussion about it in c-client list at least.He mentioned a new format in passing on the comp.mail.imap group, still in the experimental stage.