After upgrading to version 14.0, I find that archiving a single email from any folder now takes maybe 10 times as long: Was (very quick: partial second), now (about 3 seconds, maybe more). This is all local to my hard drive: The emails arrive by pop3. This happens from inbox, but also from any other folder (I tested a large selection of one folder, one email...) This is not the case when I delete an email, nor when I drag it to a different folder, but it is approximately equally slow when I drag it to the current archive folder. I use the 'a' hot key but in the interest of completeness, I checked that the archive button has the same behavior now (cannot say about prior: I didn't use it then) This occurs both before and immediately after I compact folders from the file menu No extensions, default appearance, plug ins seem to be all about Firefox Here's ls -l of the Arcives.sbd: 570% ls -l Archives.sbd/ total 395488 -rw-r--r--@ 1 /obscured/ staff 10159604 Jan 31 21:21 2009 -rw-r--r--@ 1 /obscured/ staff 166622 Jul 22 13:16 2009.msf -rw-r--r--@ 1 /obscured/ staff 26728992 May 27 13:11 2010 -rw-r--r--@ 1 /obscured/ staff 150716 Jul 22 13:16 2010.msf -rw-------@ 1 /obscured/ staff 54566398 Apr 1 11:47 2011 -rw-r--r--@ 1 /obscured/ staff 992846 Jul 22 13:16 2011.msf -rw-------@ 1 /obscured/ staff 109085920 Jul 24 19:46 2012 -rw-r--r--@ 1 /obscured/ staff 625218 Jul 24 19:47 2012.msf While poking around, I found this: -rw-r--r--@ 1 /obscured/ staff 28442624 Jul 24 19:59 global-messages-db.sqlite which I do not recognize, but which isn't a small file. Note that it's been updated quite recently. There are no errors in the error console, but there are a large number of warnings, mostly about appearance issues, it seems

What version of TB did you use before the upgrade? The global-messages-db.sqlite file is the index of your messages (for the global search box). It is updated whenever any message changes (or comes in). You can go into tools->activity manager to see if any big indexing is in progress.

Immediately before the upgrade, I was using 13.0.1 20120614161456 Before that, 13.0 Before that, 12.0.1 Before that, 12.0 ... I think you see the pattern Indexing: I do get maybe two or three hundred emails throughout the day, and I do have filters running to refile about 90% of them, but they come in dribs and drabs, not all at once.

my first guess is antivirus SW. Does speed improve if you reinstall thunderbird from http://getthunderbird.com/ /

Wayne's first guess is right on the money. I'm running a free Avast! version. I had thought it wasn't Avast! because I had the email checker turned off. Toggling file system checking, however, toggles the speed issue. Sorry for the noise.

You use Avast on OS X? It probably checks the whole file every time you add a new message to your 100MB archive folder. Maybe you could leave the filesystem checker on, just exclude the archive folder from scanning.

:aceman's suggestion was hard to follow because of the somewhat lame Avast UI for excluding files, but it worked like a charm.

We mark FIXED only when there is a code fix on TB's part :)