[RCU] Slow displaying INBOX with thousands emails

Alexey alukardd at alukardd.org
Thu Oct 25 11:50:23 CEST 2018

Ok, I trace it with imap_debug option.

First level of slowness was `thread` mode. [UID THREAD REFS US-ASCII 
ALL] 1s
Second level of little slowness was `sort by date`. [UID SORT (ARRIVAL) 
Final query looks like this: [UID SEARCH ALL] 0.1s

But how 1 + 0.7 became 3.5s of `waiting` request time? (I get it from 
profiler in browser)

And is there in chance to increase performance without disabling 

On 2018-10-25 08:55, A.L.E.C wrote:
> On 10/24/18 7:59 PM, Alexey wrote:
>> I have user with approximately 500000 emails in his INBOX folder and 
>> this is not limit.
>> And there is some inconvenience in viewing this folder. It takes about 
>> 5-7 seconds to
>> display list of emails in folder.
>> Pagination is set to 100 emails per page. I checked that IMAP server 
>> complete request
>> "FETCH 1:100 ENVELOPE" in 147ms, and "FETCH 1:* ENVELOPE" in 6 second. 
>> This is why I begun
>> to think that RoundCube may request for all emails instead of 100. 
>> Roundcube is configured
>> for default sort order: descending by receiving date.
> Try with disabled or just different sorting (in messages list options
> menu). Enable
> imap_debug to see in the log what imap commands are used and with what 
> timing.

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