Hi,
I finally deployed a migration test plant and done some conversions last night, so I took the chance to collect some data of these tests.
I've set up a virtual machine with a dovecot 2.0.13 installation in order test the mailbox conversion.
This machine has two adicional disks, one with the source data and other to store the conversion results. The source data is a restore from the latest production Maildir backup and I did a conversion to sdbox, and then to mdbox.
I attach DiskIO and CPU plots for both conversions
orange Line is read from source disk, blue line is write to destination. sdbox on the left and mdbox on the right.
Ok, this is a conversion process and not actual mailbox usage. And lacks info on how does dbox behaves in read operations.. but this is what I got for now.
[image: Inline image 1]
[image: Inline image 2] Miguel
On Thu, Mar 29, 2012 at 12:16 PM, Miguel Afonso mafonso@hangas.net wrote:
On Thu, Mar 29, 2012 at 12:30 AM, Timo Sirainen tss@iki.fi wrote:
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.
I was considering using the imaptest tool to simulate IMAP activity. I would keep the same machine configuration, only varying the mailbox format while running imaptest against each setup for a few hours/days.
I'm now converting the original Maildir format to both dbox formats and I'll give it a try. I'll share some graphs afterwards.