dovecot - Sep 2017 - questions about maildir to mdbox migration

Hi folks!  I converted some of the spools on my mail server from
maildir to mdbox.  It went smoothly and the performance has been great.
However, I have two questions regarding the process.

  First, I failed to notice the fairly low default mdbox_rotate_size,
and I changed it in dovecot.conf after the migration.  Is it possible to
somehow make that change retroactive, to coalesce the couple thousand
"storage/m.*" files that are anywhere from a few hundred bytes up to a
few megabytes, into a smaller number of larger files, without re-doing
the migration?

  Second, I'd like to delete the old maildir files and directories to
reclaim the space in the filesystem, but it's not clear to me which ones
I can safely delete, i.e. ones upon which my new mdbox-based spools no
longer depend.  I know maildir uses new, tmp, and cur directories, but
in the spool directory there are also files like dovecot-uidlist,
dovecot-uidvalidity, dovecot.index.cache, dovecot.index.log,
dovecot.mailbox.log, as well as separate directories for each of my mail
folders containing their own new, tmp, and cur directories and their own
dovecot* files.  Can someone offer some guidance regarding which ones I
can safely remove?

            Thanks,
            -Dave

-- 
Dave McGuire, AK4HZ
New Kensington, PA

Hi there ! Please tell how did you do the migration ? I tried to do
this with dsync and performance was far from 'smooth and great'.

2017-09-29 0:54 GMT+05:00 Dave McGuire <mcguire at
neurotica.com>:
>
>   Hi folks!  I converted some of the spools on my mail server from
> maildir to mdbox.  It went smoothly and the performance has been great.
> However, I have two questions regarding the process.
>
>   First, I failed to notice the fairly low default mdbox_rotate_size,
> and I changed it in dovecot.conf after the migration.  Is it possible to
> somehow make that change retroactive, to coalesce the couple thousand
> "storage/m.*" files that are anywhere from a few hundred bytes up
to a
> few megabytes, into a smaller number of larger files, without re-doing
> the migration?
>
>   Second, I'd like to delete the old maildir files and directories to
> reclaim the space in the filesystem, but it's not clear to me which
ones
> I can safely delete, i.e. ones upon which my new mdbox-based spools no
> longer depend.  I know maildir uses new, tmp, and cur directories, but
> in the spool directory there are also files like dovecot-uidlist,
> dovecot-uidvalidity, dovecot.index.cache, dovecot.index.log,
> dovecot.mailbox.log, as well as separate directories for each of my mail
> folders containing their own new, tmp, and cur directories and their own
> dovecot* files.  Can someone offer some guidance regarding which ones I
> can safely remove?
>
>             Thanks,
>             -Dave
>
> --
> Dave McGuire, AK4HZ
> New Kensington, PA

On 09/28/2017 04:00 PM, ????? ????? wrote:
> Hi there ! Please tell how did you do the migration ? I tried to do
> this with dsync and performance was far from 'smooth and great'.
  I used dsync, and had no difficulties.  Here is an excerpt from my notes:

--------------------------------------------
To change mail spool format for user at domain:

Change spool type in dovecot.conf or in database, making note of
original (current) spool type.  Then:

dsync -u "user at domain" mirror "spooltype:/spool/location"
dsync -u "user at domain" mirror "spooltype:/spool/location"
(repeat, to
pick up any changes since first run)
--------------------------------------------

                 -Dave

-- 
Dave McGuire, AK4HZ
New Kensington, PA