Am 26.01.2023 21:25 schrieb Marc <Marc@f1-outsourcing.eu>:

>
> Generally speaking the setup performs OK, I wrote a JMeter Roundcube script to
> test the Roundcube. This includes actions like listing mails and fetching
> them. I am hitting a somehow dubious limit of 600 req/s though. (This includes
> all kinds of HTTP calls to Roundcube, not only the ones triggering IMAP). When
> the dovecot becomes unavailable, the performance without mails jumps to 7700
> req/s. Testing is done with 4 JMeter-servers and one client.
>

Should you not be testing also dovecot performance directly? So you can see what is it's maximum. I can't imagine http interfaces are the bottle neck.

Right, I also set up imaptest and tested with that. I seem to hit a limit around 600 auth/s (auth workers 64, hashing algorithm does not seem to matter, tried all 3) and get about 1100 append/s and 1100 fetch/s.

But I must say that the imaptest ran in parallel (10) for the append and fetch test on a single machine. Now that I think about it, the auth test may have been limited by the single imaptest instance, as I did not run that in parallel.