Mail.app slow down

[UKenGB]

Running Mojave on cMP 4,1=>5,1 and for the most part it's working well. I have the audio stutter problem, but that should be fixed with the install of some later CPUs. But...

Maill.app slows down. E.g. if I start it in the morning it runs fine at good speed. Selecting a different message displays it almost instantaneously. Then after 1 or 2 days (sleeps over night) I notice it is slow and eventually just selecting e.g. the next message in the list can take 10 seconds or so to display the message content. When simply trying to quickly flick though messages to see what to keep or trash etc, the slowness becomes intolerable and I have to Quit the app, then re-start it. After which it runs at full speed for another day or so.

Just to be clear, I doubt it runs at full speed then suddenly slows right down. I suspect it gradually slows down after it starts, until it becomes noticeable and then unacceptable and I have to re-start the app.

Anyone else experiencing this and/or any idea of the cause and how to eliminate the problem?

 

[yukari]

I suspect this is related to sleep/wake cycle issue others are having, including myself.
See: https://forums.macrumors.com/threads/slow-performance-after-wake-from-sleep-clamshell.2184388/

Even in non-clamshell mode, it seems to slow down to a point of non-usable after sleep/wake cycle.

 

[UKenGB]

I suspect this is related to sleep/wake cycle issue others are having, including myself.
See: https://forums.macrumors.com/threads/slow-performance-after-wake-from-sleep-clamshell.2184388/

Even in non-clamshell mode, it seems to slow down to a point of non-usable after sleep/wake cycle.

Hmm, interesting. I'm quite prepared to believe this is more widespread than just with MacBook (Pro)s, but in my case it is definitely Mail that has the problem. I say that, but it is likely to be what I'm most using and hence notice it. However, it is apparent that quitting and restarting Mail.app fixes it. Whereas when it slows, just selecting a different message can take 10 seconds before it displays on the screen (odd because while you wait the displayed message is NOT the one selected in the list which can be confusing). But after restarting Mail, selecting messages updates the screen almost instantaneously.

I wonder if the other's problems are similarly Mail.app related.

I do wonder though about Apple's response to such problems. Appearing to just want to ignore it and merely sweep it under the carpet. But I suppose they have better things to do, like designing new Memojis.
[doublepost=1559894501][/doublepost]

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BTW, is that you on the Monster 1200R?

 

[yukari]

I wish that was my Monster 1200R.
I have Kawasaki Ninja customized with red fairing. So it sort of looks like the one in my Avatar. But I do have the full red/black outfit for safety.

 

[Honza1]

Hmm, interesting. I'm quite prepared to believe this is more widespread than just with MacBook (Pro)s, but in my case it is definitely Mail that has the problem. I say that, but it is likely to be what I'm most using and hence notice it. However, it is apparent that quitting and restarting Mail.app fixes it. Whereas when it slows, just selecting a different message can take 10 seconds before it displays on the screen (odd because while you wait the displayed message is NOT the one selected in the list which can be confusing). But after restarting Mail, selecting messages updates the screen almost instantaneously.

I wonder if the other's problems are similarly Mail.app related.

Probably not. This slowdown is very specific issue, related to external Thunderbolt docks connected to machine which, after long enough sleep time, that computer falls into deep sleep, somehow does not wake up enough. These cases seem to be rare enough, that if you try to google it, you will find my posts (with few "me too" contributors) and may be two or three other threads in other forums. Basically very rare - if this was common, there would be lot larger uproar.

When this general slowdown happens (as reported e.g., in https://forums.macrumors.com/threads/slow-performance-after-wake-from-sleep-clamshell.2184388/) the ONLY way to recover is reboot. And more or less that requires hard reboot. Killing Mail does absolutely nothing, if anything, you may not be willing to wait for Mail to die.

 

[UKenGB]

Ok, not related then. So what is Mail.app doing?

After my last post, Mail was a bit slow so I ran Activity Monitor and when I brought Mail.app to the front, it was using 116% CPU time. Not sure how that's possible and it soon dropped, but often spiked again at 40% or so.

Since then, having recently quit and restarted Mail, I just checked again and AM showed a 70% peak when bringing Mail to the front, then down to 20 and a bit of 10 before dropping back down the list at very little CPU usage.

While 70% is not as bad as 116%, it still seems very high to me. It's only an email app after all.

kernel_task seems to be consistent at about 20%. Since this is an 8 core cMP, that's a lot of processing. Doing what?

Anyone any clue why Mail gets so gummed up after a few days?

 

[Honza1]

Ok, not related then. So what is Mail.app doing?

After my last post, Mail was a bit slow so I ran Activity Monitor and when I brought Mail.app to the front, it was using 116% CPU time. Not sure how that's possible and it soon dropped, but often spiked again at 40% or so.

Since then, having recently quit and restarted Mail, I just checked again and AM showed a 70% peak when bringing Mail to the front, then down to 20 and a bit of 10 before dropping back down the list at very little CPU usage.

While 70% is not as bad as 116%, it still seems very high to me. It's only an email app after all.

kernel_task seems to be consistent at about 20%. Since this is an 8 core cMP, that's a lot of processing. Doing what?

Anyone any clue why Mail gets so gummed up after a few days?

And did you try to do "Rebuild" for each of your mailboxes? Select mailbox and it is in the Mailbox menu.

If that does not help: One more idea on this. Warning: you will not like it.

Few years ago my Mail went bit bonkers on me and behaved, well, strange. Do not remember how much cpu it used, but it was having challenges to find mails, count unread messages, move messages around... Turns out, it had corrupted its database. It is an ugly thing which stores and indexes individual messages inside. It is possible you have corruption of the database and Mail is having difficulties with indexing etc. It can easily run serious amount of cpu when it has such difficulties.

I ended up googling this and found instructions how to resent my Mail database (may be even from Apple itself, do not remember). Make sure you have one which is for recent version of Mail. Instructions may change. Not sure what exactly steps were, but in short - I had to export my local mailboxes out somehow into some containers, wipe the existing database and setup everything from scratch. Cleaned up lots of space as there were old messages never deleted from my mail system. Lost my customizations to mails (keywords, labels,...)

Keep in mind that this can happen anytime, those databases can get corrupted by some disk error at any time and with any number of messages. Clearly happens rarely, it is rarely discussed.

If you keep all your mail on server, this should be trivial. Reset and wipe local stored messages and re download from server. But. if you have (like me) lots of local mail saved, this is pain. But it helped and my Mail behaves since.

 

[UKenGB]

That sounds very plausible and probably what I need to do. All my mail is either in iCloud or my local server and none of it 'on my Mac', so I just need to clear the local cache and start again. Not sure how to safely do that at present, but I'll look into doing that and see if with the freshly built database Mail can keep running at a decent speed.

Thanks for that pointer, I'll respond here once I've tried that in a few days' time as I'll be away.