[Dovecot] Deleted mails in dsync backups

[Wolfgang.Friebel at desy.de]

Hello

we are doing regular backups of the mdbox mail folders using

dsync -u username backup mdbox:/somedir/BACKUPS/username

(still with version 2.1.10, but 2.2.5 is in testing phase)
We do observe that the directory size in the BACKUPS directory is 
growing with respect to the original mail folders. I believe this is due 
to deleted mails not being purged in the backup. We are doing regular

doveadm purge -A

cleanups, but this does (of course) not affect the backups and subsequent 
dsync backup runs seem not to clean up deleted mails in the backup either.

Will the behaviour of the dsync backup command deal with deleted mails in 
the 2.2.5 release? If not, what could we do to get rid of the deleted 
mails in the backup (or is there another reason for the growth in size)

We have e.g. after 9 month of running with 2.1.10

du -sk username
588520
du -sk /somedir/BACKUPS/username
863024

-- 
Wolfgang Friebel
Deutsches Elektronen-Synchrotron DESY