305785 - Reading of imap mail slows down after awhile

Status: RESOLVED WORKSFORME

(Thunderbird :: Mail Window Front End, defect)

Description

[Chris Andrichak]

User-Agent:       Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en) AppleWebKit/412.6 (KHTML, like Gecko) Safari/412.2
Build Identifier: version 1.0.6 (20050716)

I currently have two imap accounts in Thunderbird. After a while of reading mail in either, the performance 
of just reading messages seems to slow down greatly. It does not matter what type of message or if they 
are new or already read. What does help is if I Quit the program, delete the on disk mailbox indexes 
(*.msf) and restart the application. Then reading performance is quite snappy again for a few days.

Not quite sure if this would be the same as bug: 277381

Reproducible: Always

Steps to Reproduce:
1. after reading mail for a few days (imap account), notice reading performance degrade
2. Quit the program
3. delete the on disk mailbox indexes 
4. restart the application

Comment 1

[Chris Andrichak]

To preempt any comments, I am pretty much constantly purging deleted messages from my folders. And I 
rarely have more than 100 messages in my in box at a time. Performance after I delete an index file is fine, 
but it will slow down to nearly unacceptable after a few days.

Comment 2

[Chris Andrichak]

Happens in the 1.5 beta also, I would almost say the slowdown happens more quickly but I just started 
using the new version. I also have not yet tried deleting the index files (with the new version).

Comment 3

[Chris Andrichak]

Duplicate/related?
https://bugzilla.mozilla.org/show_bug.cgi?id=277381

Comment 4

[Chris Andrichak]

Deleting local index and other files relating to the IMAP accounts greatly speed up the client performance 
with this version also.
Slowness seems to come after a couple days of leaving the client running connected but having the 
computer put in and out of sleep at various points.

Comment 5

[Chris Andrichak]

It seems that if I leave Thunderbird running and put the computer to sleep, after I wake it back up it has 
the slowness problem. If I watch the CPU percentage in the Activity Monitor (graphical top) during normal 
functioning, reading messages will bring Thunderbird from a steady state CPU percentage of .30% to 
about 25% for an HTML message. If I put the computer to sleep and wake it up again, reading HTML 
messages makes the program peak at about 65% CPU. If I then quit Thunderbird and relaunch it, the peak 
reading percentage goes back down to 25% or so.

As an aside, I wonder if the .30% steady State utilization is because of the WaitNextEvent sleep time being 
set to 0: https://bugzilla.mozilla.org/show_bug.cgi?id=141710

Comment 6

[Chris Andrichak]

problem doesn't seem to be happening anymore, TB v2.0.0.4

Comment 7

[Chris Andrichak]

Also, last TB 1.5.x version I used didn't seem to have this problem anymore either.