> On 1. Dec 2021, at 0.30, Einar Bjarni Halldórsson <ei...@isnic.is> wrote:
>
> Hi,
>
> We're migrating our mailboxes from Zimbra to dovecot, running on FreeBSD
> 12.2. We're using mdbox and solr for fts. dovecot version 2.3.17.
>
> One of our mailboxes gets a bcc of every outgoing mail from our system and it
> currently holds ~4.5 million messages taking 30 GB.
>
> One of the ways we use the mailbox is that when outgoing mail is sent, we
> store the Message-ID in our database, and in our admin interface we can open
> the mail and it's fetched from IMAP by doing a 'SEARCH HEADER Message-ID
> <MSG_ID>'.
>
> In Zimbra this was reasonably fast, but after migrating the mailbox to
> dovecot it's 30 seconds which I think we can reduce.
>
> After turning on mail_debug I see this in our log
> https://pastebin.com/kP9H7gSB
>
> Looks like solr finishes searching instantly, then there's ~30 seconds of
> silence in the logs, and then more log lines about fetching data from mail
> cache.
>
> The same thing happens if I use telnet and just issue a 'SEARCH HEADER...'
> command.
>
> How can I find out what dovecot is doing in those 30 seconds?
Did you have Messsage-ID listed in mail_always_cache_fields when you imported
the mailbox?
Do you have it now?
If not, please add it and then use doveadm fetch to populate that in cache.
I think the correct setting is
mail_always_cache_fields = hdr.message-id
But you also might want to add some other fields
Sami
