There is a old bug that we are aware. Maybe we look at it again.
Aki
> On 16/08/2022 16:21 EEST Aleksander Machniak wrote:
>
>
> On 15.08.2022 11:43, Ewald Dieterich wrote:
> > The following IMAP SORT with 2 sort criteria is very slow on an mdbox
> > mailbox with lots of mails (more than 10,000) and an empty cache:
> >
> > . SORT (ARRIVAL DATE) UTF-8 ALL
> >
> > Each mail is opened when the SORT is executed, which is slow, given the
> > number of mails in the mailbox.
>
> There might be a bug, but "SORT (ARRIVAL DATE)" itself does not make
> much sense. It means "sort by arrival timestamp and for all messages
> with identical arrival timestamp use Date header instead".
>
> --
> Aleksander Machniak
> Kolab Groupware Developer[https://kolab.org]
> Roundcube Webmail Developer [https://roundcube.net]
>
> PGP: 19359DC1 # Blog: https://kolabian.wordpress.com
