Thunderbird hanging while downloading messages

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tanstaafl
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Joined: July 30th, 2003, 5:06 pm

Re: Thunderbird hanging while downloading messages

Post by tanstaafl »

"This is the built-in virus protection/malware in Windows 10. Shows up working hard as a process in Task Manager."

The antimalware service (MsMpEng.exe) consistently takes 0% CPU usage and 37MB of memory on my windows 10 Home Build 1809 PC. Its listed in background processes, not apps, in task manager. "real time protection" in settings -> windows security -> virus & threat protection -> virus & threat protection is grayed out. I assume that is because I'm configured to use BitDefender as my anti-virus scanner.
garyfritz
Posts: 256
Joined: July 30th, 2007, 9:20 am

Re: Thunderbird hanging while downloading messages

Post by garyfritz »

Ah. (Should have thought to check the CPU usage long ago, duh)

@taanstafl, your MsMpEng.exe was probably using 0% because you have BitDefender. MsMpEng.exe has nothing to do.

I sent & downloaded some large messages. The Antivirus Service was running, but it was only consuming 8-10% of CPU. Unfortunately I'm not sure that was a valid test. It's a bit hard to test this, because I never know when I'm going to have lots of messages to download. And for some reason when I send a set of test messages, they download fast. I just tried sending myself 5 message, and they downloaded instantly. It's almost like something gets cached, and everything works fine until the cache finally gets dropped. So some time later, when it's totally slipped my mind, I'll download email and wham! Dog-slow. So I'll wait for that to happen and check the CPU usage.

Not sure why MsMpEng.exe is so problematic, but only for a few users...
jes1974 wrote:Since I keep a copy of all my mail on the server (except some archives), I just backed up, deleted the profile, redownloaded into maildir. You could copy off folders to a local archive and copy them back.
Downloading into the new maildir folders is probably best. I have lots of mail history and limited space on my mail server, so I keep a lot of older/larger stuff in Local Folders. I assume those would not be involved in the mail-download process (and would not have to be re-built in maildir format??) so I don't have to do anything with them except copy them somehow and load them into the new install directory.

I'm working out of town this week and my network access is not very speedy so I might wait a while to try the install & re-load step.
garyfritz
Posts: 256
Joined: July 30th, 2007, 9:20 am

Re: Thunderbird hanging while downloading messages

Post by garyfritz »

Gack. My mail server got slow/hung for a few minutes this morning. That somehow confused Thunderbird, and it decided it needed to re-download everything. EVERYthing. Thousands of messages. After a couple of hours it finally finished downloading 1000 messages in Inbox, but then it started in on my Sent folder. Which is big, but it's not the 180,000 messages that TB tried to download. At that rate it would be downloading for a month.

I finally killed it and re-started it, and so far it hasn't started another download spree. But geeze...

Question: the recommended way to do the conversion to maildir is to delete the profile, create a new profile that uses maildir format, and re-download your folders. Which should hopefully go a whole lot faster than it does currently. But the profile also contains your Local Folders? How do I back those up and restore them? All the backup procedures I see back up (and restore) the entire profile. Can I just copy the Local Folders directory to the new profile?
jes1974
Posts: 3
Joined: March 11th, 2019, 10:08 am

Re: Thunderbird hanging while downloading messages

Post by jes1974 »

But the profile also contains your Local Folders? How do I back those up and restore them? All the backup procedures I see back up (and restore) the entire profile. Can I just copy the Local Folders directory to the new profile?
Sorry, left that step out. Once your new profile is loaded (and you're happy with the performance), copy the old local folders directory (under /./Mail/Local Folders) into the new profile.

After doing this on several machines, I would just delete the mail account in thunderbird and recreate it (after making at least one full backup of your profile).
Also from several machines, it seems to make the biggest difference on RAM-limited machines. Once your mailfile doesn't fit nicely into RAM (with a lot of overhead for the virus/malware scanning), I seem to see the problem. People with 50MB mailfiles who don't see this problem aren't going to. On a 8GB machine, I barely saw the problem. On an SSD machine, it was 5x faster (but still 25x slower than "normal") probably because RAM paging was so much faster.
garyfritz
Posts: 256
Joined: July 30th, 2007, 9:20 am

Re: Thunderbird hanging while downloading messages

Post by garyfritz »

Thanks, I will plan to do that. (Bit swamped right now but I'll put it on the list.)

Oddly enough, my system has been behaving much better for the last month or so. I haven't noticed any excessive download times. I think it's taking longer than it should, but it's minor enough that it's not annoying. Don't know why but I'm not complaining!

My laptop has 16GB of RAM and my largest mboxes are about 500MB, so that shouldn't be a problem.
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