[Dovecot] Dovecot performance under high load (vs. Courier)

[Timo Sirainen]

On 23.6.2012, at 13.21, Ed W wrote:

>>> But I don't know, whether this is the sort of caching you are referring to.
>> 
>> what's a point of caching imap, except your webmail service is not locally connected (localhost or LAN) to imap server?
> 
> Asking for items 600-615 from a threaded list, sorted by something, can be an expensive operation, especially if you just asked for items 585-600 a moment ago?

Can be, but is it? :) Dovecot attempts to cache/index stuff as well. Normally there shouldn't be a need for extra caching layer except in cases of higher network latency.