I'm looking for an imap server that is fast with larger folders. Say 20'000-100'000 emails per folder.
Currently I'm using dovecot, and opening a folder can take 10 seconds, and the HD light on the imap server is brinking like crazy.
I'm using alpine as a client, and it only lists the newest mails by default, so it's not that my client is trying to transfer everything when opening the mailbox. This can be seen in that when I scroll it has to load the subject lines for the next page (the first time I scroll there).
I'm using maildir on XFS.
Edit: I ask since it's not much data, in the grand scheme of things. If this was in a SQL database then getting the subject lines of the newest 40 messages would not take 10 seconds for a folder of 40'000 emails. The only data needed is:
SELECT date, from, subject FROM emails ORDER BY date DESC LIMIT 40;