dovecot - Jun 2010 - Migration from Courier to Dovecot: is it recommended to "force" d.index* creation?

Hello,
we are planning to migrate from Courier to Dovecot.

We already know courier-dovecot-migrate.pl, that will convert UID list 
and subscriptions files to dovecot format, and we will run it in batch 
on all Maildir + enable it at login, once we do the switch

But we are also wondering it it might be wise to "force" the creation
of
dovecot.index{,.cache} files at conversion-time. It seems that, at 
least, d.i.c is created at FETCH of a mail, i.e. reading it, but we do 
not want to "alter" mails status of our clients.

Is there a way to create them in batch, or is it better to just let them 
be created once clients start accessing their mailboxes via dovecot?

Thanks in advance,
Sandro

On ti, 2010-06-08 at 14:07 +0200, Sandro Tosi wrote:
> But we are also wondering it it might be wise to "force" the
creation of
> dovecot.index{,.cache} files at conversion-time. It seems that, at 
> least, d.i.c is created at FETCH of a mail, i.e. reading it, but we do 
> not want to "alter" mails status of our clients.
> 
> Is there a way to create them in batch, or is it better to just let them 
> be created once clients start accessing their mailboxes via dovecot?
Problem is, the contents of cache files depends on what client is being
used. You could of course try to fetch the most commonly used fields
that clients use. Anyway, it's probably not a big deal. The worst that
can happen without index files is slightly higher load temporarily than
what it would have been under Courier.

With v2.0 you could do this pretty easily with doveadm command, but with
v1.x there's no super easy way to do it.