running cyrus-imapd over openstack cloud storage ?

[Riccardo Veraldi]

Hello,
I ask if anyone ever tried cyrus-imapd /var/spool/imap partion over an 
openstack cloud storage.
I have such an idea to try it but if anyone already did it, I wanted to 
ask if this can slow the cyrus-imap
access to file and folders, or if this is just good for a sort of imap 
storage reiliability.

I have to implement an imap server for about 10000+ mailboxes.
any hints on the architecture I might use ?

thank you

Rick