Refreshing dovecot virtual folders

Question

I've created several virtual folders in my dovecot setup. Influenced by gmail I collected all my email in All and then created a virtual folder containing unread and flagged emails, together with all mails that reference such emails (inthread refs (or (or recent unseen) flagged)). This works beautifully, I see all the emails I expect to see when pointing mutt to the mailbox. However, the virtual folder doesn't seem to refresh after I make changes; I've removed all flags on several of the email threads and I expected that sooner or later those threads would disappear from the virtual folder. However, about 12 hours later mutt hasn't noticed any changes in the virtual folder. Restarting mutt doesn't make any difference.

How do I get dovecot to refresh the contents of the virtual folder? (Or am I simply expecting too much?)

Answer 1

I got an answer on IRC. It's possible to control where the index for the virtual folder goes, and putting it in memory causes the folder to refresh properly:

location = virtual:~/Mail/virtual:INDEX=MEMORY