Mailing List Message #101523
From: Brian Gibson <>
Subject: Re: any fix yet for Thunderbird issues?
Date: Thu, 03 Feb 2011 22:53:52 -0500
To: CommuniGate Pro Discussions <>
To Jim's question about the load average, it is a Unix/Linux indicator you can see from running the "top" or "uptime" command and here is an explanation of it.

"In short it is the average sum of the number of processes waiting in the run-queue plus the number currently executing over 1, 5, and 15 minute time periods"

During normal operation our server will average somewhere between 0 and 4 and it will jump up for a minute or two when a campus wide message gets sent out through the mailing lists (average jump in our case is somewhere around 10 and it lasts 2 or 3 minutes). When the Thunderbird issue starts happening it can jump anywhere from 20 to 50 for up to a couple hours at a time. I can sometimes get an idea of who the culprit is by checking the IMAP Access monitor and looking for the string "copying messages" and if someone has an IMAP connection that is doing that for an extended period of time we try and visit them and figure out the issue. What has been strange is that in some cases the people we have visited already have the proper settings enabled/disabled but their Thunderbird continues to copy messages so it makes me think there are some issues with their code.

Nicolas, thanks for the suggestions. We give our faculty, staff and students 1 GB of quota space and if I try and bring up the "lets reduce the quota discussion" it turns into the "why don't we switch over to Google Apps for Edu discussion" which isn't fun. About your second suggestion I think its a great idea to have everyone do their mass-download but like I mentioned before, I have seen people have indexing and syncing turned off and their Thunderbird client still go nuts copying down messages. Thanks for the third idea about the prefs.js file, maybe I'll dust off my vbscript book and take a whack at it, the only problem is not all of our PCs are in the domain and half of our staff use Macs. Also, people like Thunderbird so much they have been setting it up on their home machines where we have zero control.

Here are the steps we have been doing when we get to a client  (I know Nicolas you had said to do the opposite on option 3 so use my suggestion with caution).

1. Go to "Tools" -> "Options" -> "Advanced" -> "General" tab -> uncheck the option labeled "Enable Global Search and Indexer".

2. Right next to the above mentioned "Enable Global Search and Indexer" option is the "Config Editor" option, this is where you make advanced tweaks. Inside there search for an option named "mail.imap.expunge_after_delete" and make sure it is set to "false" (which is the default).

3. Under "Tools" -> "Account Settings" -> "Synchronization & Storage" uncheck the option "Keep messages for this account on this computer"

4. Go to "Tools" -> "Options" -> "Advanced" -> "Update" ->  uncheck both options under "Automatically check for updates to:".

5. Under "Tools" -> "Account Settings" -> "Server Settings" check the option named 'Clean up ("Expunge") Inbox on Exit' (should be checked by default).

6. Under "Tools" -> "Account Settings" -> "Server Settings" -> "Advanced" -> change the "Maximum number of server connections to cache" to 2 (default is 5).

I still wonder if there is a way for the CGPro developers to throttle the amount of IMAP i/o per user account (maybe by number of messages or amount of data processed per time period). That way, if a Thunderbird client wants to download all the mail for all folders and index each message they will only be slowing down their own experience.

One other person on this list had mentioned he was having the same issue and while I was comparing notes with him he said CGPro support mentioned they were going to include a fix for this in the next release but that was sometime in November or December. I had opened a case with CGPro and roughly a month ago they told me they didn't have any fix in the pipeline for this.

On 2/3/2011 9:26 PM, Nicolas Hatier wrote:
There could be other indirect solutions:

- Reduce the account quota so users are forced to delete old things. Thunderbird will take less time indexing everything.
- Ask everyone (or a set of people until everyone passed) to leave Thunderbird open over a weekend. Usage will probably skyrocket there, but then it'll be done indexing everything and further updates of the index should be less demanding.
- Maybe a startup script could check %appdata%/Thunderbird/Profiles/<profilename>/prefs.js and add
user_pref("", false);
if not present - or set to false if present. This would disable indexing.


On 2011-02-03 20:31, Shaun Gamble wrote:
On 4/02/2011 10:55 AM, Support@ish wrote:
Not sure about this, I have thousands of users on thunderbird using IMAP without issue. I would be looking at your config's as suggested in other messages

On 4/02/11 8:22 AM, Brian Gibson wrote:
Has anyone found a fix on the server side yet for the performance issues
Thunderbird 3.1 with IMAP has introduced? We got a brief rest from it
over xmas break but all the professors are back and I think yet another
upgrade to Thunderbird was recently released and the server is getting
absolutely hammered. The load average climbs up to as far as 50 and
stays there while it happens. I know the options to change on the client
but I can't keep playing whack-a-mole like this!!!!

When TB upgraded to 3.0 and then 3.1, there was an introduced issue where they index all of the emails in each folder. This causes all sorts of issues. The indexing can be switched off but only at the client. We experienced the problems. As a CGP administrator, you may not notice the problems unless you get complaints or look for them. The problem definitely exists though and is caused by TB, not CGP.

The only solution I have found is to disable the setting at each client. When you have a large number of clients with TB, this is not necessarily an easy option.


Nicolas Hatier, ing. <>
Niversoft idées logicielles -


Brian Gibson
Systems Administrator
Wheaton College

Are you a musician? If so visit my Arbans Online music site at and listen & contribute
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster