477517 - High CPU usage when IMAP server is unresponsive, until timeout

Status: RESOLVED INVALID

(MailNews Core :: Networking, defect)

Description

[Phil Miller]

Steps to reproduce:
1. Configure a mail account with incorrect IMAP server settings. In this case, connecting to imap.google.com on port 143.
2. Open the Subscribe dialog on this account
3. Watch spinner in the new window go for a while with no progress occurring

Expected result:
1. Thunderbird uses minimal CPU time during this interval (i.e. enough to make the spinner go).
2. Get a message that a connection could not be made after a time.

Actual results:
1. CPU usage for Thunderbird and X shoot up, and stay high until either the connection times out (with a dialog box indicating such), or I hit 'Cancel'
2. Timeout interval feels really long.

Likely related: #293570, which got auto-closed a few years ago because no one bothered to address it.

Comment 1

[Phil Miller]

To be clear, the problem with the server mentioned is that it resolves, but will neither open a connection nor indicate that the port isn't open. In this case, 'telnet imap.gmail.com 143' times out, too.

Comment 2

[Wayne Mery (:wsmwk)]

Phil, can you reproduce with beta 2 ?
http://www.mozillamessaging.com/en-US/thunderbird/early_releases/

Comment 3

[Phil Miller]

In Beta 2, the results aren't as bad, but this is still present. Thunderbird still runs ~25% of a CPU (on a Core 2 Duo 2.33 GHz), and Xorg another 10-20%. So, it's no longer severely detrimental to system usability, but it's still bad.

Comment 4

[Wayne Mery (:wsmwk)]

(I hesitate to ask a second time but)
Phil, how does this look with v3.0.1?
bienvenu, would we want a log?

Comment 5

[Phil Miller]

I'll give it a try later this evening. Is there particular cause to expect a change?

Comment 6

[David :Bienvenu]

A log is probably not that useful since we won't be connecting to the imap server.
I don't know of anything that would have changed in this area...Is bringing up the subscribe UI different from clicking on the inbox for the misconfigured account?

Comment 7

[Wayne Mery (:wsmwk)]

Phil??

(In reply to comment #6)
> Is bringing up the subscribe UI different from clicking on the inbox for the misconfigured account?

Comment 8

[Wayne Mery (:wsmwk)]

> (In reply to comment #6)
> > Is bringing up the subscribe UI different from clicking on the inbox for the misconfigured account?

Phil indicates he will be testing this soon. (bumping this back to UNCO for now)

Phil, when you do test, please consider using the newest possible code, eg an early build [1] or a nightly build [2], with precautions of backing up your thunderbird profile, etc. Thanks.

[1] http://www.mozillamessaging.com/en-US/thunderbird/early_releases/
[2] ftp://ftp.mozilla.org/pub/thunderbird/nightly/latest-comm-central/

Comment 9

[Phil Miller]

Just tested 3.0.11 (distributed as Icedove by Debian), and it no longer spins. There's a different UI bug (it quickly fails to connect, but nothing actually says so), but that should be a separate report.