309597 - Thunderbird open too many IMAP connections

Status: VERIFIED WORKSFORME

(Thunderbird :: Mail Window Front End, defect)

Description

[Gerard Earley]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.2; en-GB; rv:1.7.12) Gecko/20050919 Firefox/1.0.7
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.2; en-GB; rv:1.7.12) Gecko/20050919 Firefox/1.0.7

Just tried to use the 1.5b1 and have found that the client is opening an unknown
number of IMAP connections. This is to a local courier IMAP server which had
previously allowed 16 connections per IP. I have increased this to 64 but with
no success.

Reproducible: Always

Comment 1

[Jo Hermans]

*** Bug 309598 has been marked as a duplicate of this bug. ***

Comment 2

[David :Bienvenu]

How many accounts are you accessing on this server? Thunderbird limits itself to
5 connections per account on any given server; I tried it with today's build,
and that limit seems to be working fine. You can change the limit per account in
the advanced imap server settings.

If we're caching more than 5 connections for any given account, that would be a
bug. Is that happening? If so, can you attach an imap protocol log showing that,
by following these instructions:

http://www.mozilla.org/quality/mailnews/mail-troubleshoot.html#imap

Comment 3

[Henrik Skupin [:whimboo][⌚️UTC+1]]

I can confirm that with Tb RC1 WinXP - version 1.5 (20051025).

It's very annoying. I have two IMAP accounts. While the first one is working fine, I'm not able to work properly with the second one. I've only 5 folders (inbox,drafts,sent,junk,trash) and I can only open the first three ones. The number of connections I could increase but without any change. The error is still reported.

That's definetely a regression because I havn't seen that anytime before. For myself I'm unable to use one of my most important IMAP accounts.

I can create an IMAP log. Mscott how important is that bug for you? Dunno how many people will be envolved with that bug when they switch from 1.0.x to 1.5.

Comment 4

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Attachment: IMAP log

I tried to open inbox, drafts and sent. When clicking on the last folder, the error message appears.

Comment 5

[David :Bienvenu]

Did you try reducing the number of connections we cache from 5 to 4 (or 3)? account settings | server settings | advanced.

1.07 didn't open more connections; it just failed silently w/o an error message, often with bad results.

Comment 6

[Henrik Skupin [:whimboo][⌚️UTC+1]]

(In reply to comment #5)
> Did you try reducing the number of connections we cache from 5 to 4 (or 3)?
> account settings | server settings | advanced.

Not yet, but after I changed the number of cached connections to 4 no error is reported. What's the default number of connections by IMAP servers? Or why do we fail? The IMAP server I'm using at the moment is Courier over a tunneled ssh connection.

A similar error message is shown sometimes when I try to delete a message on my first account. But that is not always reproducable.

Comment 7

[David :Bienvenu]

The *only* imap server that I know of that limits the number of connections per ip address is your server, Courier. It's configurable on the server, through some setting that I don't have handy. Something like MAX_PERIP...By default, with Courier, it's 4. 

The fact that reducing the number of connections tb caches makes the alert go away means that tb is functioning as designed.

One fun thing can be if you have two accounts on the same server, i.e., the same IP address. Then, you have to set the max connections we'll cache to 2 on each server.

Anyway, this is not a regression - the change was that we fixed a regression which caused the alert not to be shown. Pre 1.0 TB, the alert was shown and it was broken shortly before 1.0 was released.

Comment 8

[Henrik Skupin [:whimboo][⌚️UTC+1]]

David, you are right. Now I changed MAXPERIP to 20 and it's working fine. No problem anymore with the default value of 5 cached connections.