Roundcube Very slow to respond to using reply button

[dms2]

We are using 0.9.5 roundcube although this issue was present in 0.9.1 as well.  We are using DBMAIL 3.1.7 as the imap server.

When are user logs into roundcube it is very quick to respond and it is also very quick to open a message from an inbox.

However when a user hits "reply" to a message there is a very long delay before the "reply" becomes available.  I have not seen any errors in any logs but when I log the imap traffic I see that on hitting reply the following is repeated for every folder in the user's mail

[27-Nov-2013 14:44:26 +0000]: [FF82] C: A0007 MYRIGHTS mail
[27-Nov-2013 14:44:26 +0000]: [FF82] S: * MYRIGHTS "mail" lrswipkxteacd
[27-Nov-2013 14:44:26 +0000]: [FF82] S: A0007 OK MYRIGHTS completed

[27-Nov-2013 14:46:01 +0000]: [FF82] S: A0522 OK MYRIGHTS completed
[27-Nov-2013 14:46:01 +0000]: [FF82] C: A0523 LOGOUT
[27-Nov-2013 14:46:01 +0000]: [FF82] S: * BYE

In this logged example the whole chain took 1:30 minutes to complete before the user sees a compose box to reply to which is clearly too slow.

Is this behaviour as intended?  It seems odd to me, but I haven't logged the traffic before.

Our users tend to have a great many folders (this user has 519) and so this has basically made roundcube unusable for them and they have gone to Squirelmail which takes forever to load up but is then responsive.

[alec]

What plugins are you using? Did you try all plugins disabled?

[alec]

Sorry, it is a core feature. Looks like the only solution for you is to enable caching (imap_cache) and/or tell your users to not subscribe 500 folders.

[dms2]

I am not using any plugins.

//I tried setting imap_cache to db and it made no difference.
Edit, actually I have tried this again and realised what is happening.  When I log in as a user and hit reply with caching db on the process is as slow as usual.  However subsequent replies are much faster.  They remain fast until the user logs out and relogs in at which point the process is very slow again.

Clearly the first time I tried this I logged out between attempts.

Is there anyway to retain caching between logins?

I'm afraid can not stop my users from creating many folders, because this is how they separate their case work.

[ABerglund]

This may not work for you, but in our organization we recommend users who deal with high volumes of email use a local IMAP client (such as Thunderbird) rather than webmail. Not all users are good candidates for a web-based client, regardless of how well-developed it is.

[dms2]

Thank you, but we have users using thunderbird, outlook, roundcubemail, their handsets etc etc, anything which they find convenient.

Given roundcube loads much faster than squirrelmail most users prefer it as a webclient, but this issue which has crept up with the reply delay is very inconvenient.  It looks like stopping the deletion (I assume this is happening) of the cache between sessions would fix the problem for me.

[alec]

I created a ticket for this issue, http://trac.roundcube.net/ticket/1489451. I think we might have a solution soon.