[Dovecot] dbox vs. mdbox

[Timo Sirainen]

On 28.3.2012, at 13.13, Hangas wrote:

> Timo Sirainen <tss <at> iki.fi> writes:
> 
>>> 4. Are there real-world benchmarks showing measurable differences between 
>>> maildir, sdbox mdbox?
>> 
>> Not that I'm aware of. So far everyone I've tried to ask have replaced their 
>> whole mail system and their storage, so the before/after numbers can't be 
>> compared. I'm very interested in knowing myself too.
> 
> I think I can give my contribution here.  I'm planning to migrate from dovecot 
> 1.x to 2.x.  Currently, on 1.x I'm using Maildir as this was my best choice at 
> the time, but now I'm trying to decide the mailbox format for a 2.x 
> fresh install.
..
> My ideia is to install a fresh server and replicate the production maildir on it 
> to build a test "source disk" that I'll use then to experiment the conversions 
> to sdbox and mdbox.
> I then plan to test the performance of the dbox formats, but I can include 
> Maildir measurements just for the record.
> 
> I'm open to suggestions on how to test this properly

The main problem is that it's difficult to do any "real world" tests with IMAP, especially when users are using many different kinds of IMAP clients. So I'm very interested in hearing some numbers (and disk IO graphs for a few weeks would be great) before your migration and after your migration, but the numbers for your tests might not mean all that much.