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kennedy · May 19, 2009, 08:07 AM

Most of the time when I switch mailboxes, it takes about 3 minutes! (The message header list and mail message area are both blank during that time.) Sometimes it is quick though... instantaneous.

After that, when I switch to a different message by clicking on it in the header area, it takes 40-65 seconds to switch! (The message area shows "Loading" with a spinner during that time.) Sometimes it is quick though... instantaneous.

This is switching between small (2KB) messages. If I switch to a message that has 1MB of text in it, still about the same speed. But if I switch FROM a message with 1MB of text in it, no matter whether I am switching to a small or large message, it can take 5 minutes. Sometimes it is quick though.

Watching Activity Monitor during the above, I note Mail's CPU usage jump as high as 10%... but in all, the CPU is never fully utilized. There is no paging going on. There is some disk activity, but fairly light. And some network activity, but fairly light. So, there seems to be no resource contention to blame. Mail just seems to be waiting on something that is real high latency... for no apparent reason.

Suggestions?

besson3c · May 19, 2009, 09:17 AM

What does Mail's activity monitor show itself doing?

If your mailboxes have enough messages in them, you may have to simply stop using Mail as I was forced to do.

infowarrior · May 19, 2009, 01:40 PM

Try this --

Is Apple Mail running slow? Speed it up

...worked wonders for me.

kennedy · May 20, 2009, 11:31 AM

Leaving Mail's Activity window seemed to fix the really long delays... (Murphy's Law of Bug Reproduction). So, I hadn't seen anything yet other than normal behavior.

But then I tried the suggested "vacuum" of my Envelope Index. Does seem a bit snappier now... but much more testing is needed to say for sure... and whether the really long delays are gone for good.

In any case, THANKS for the suggestions.

Big Mac · May 20, 2009, 12:56 PM

How many messages do you have in the folders?

Archiform 3D · May 20, 2009, 02:19 PM

Could it be that you are using IMAP to get email and not POP? This could slow things down considerably. I run IMAP on one of my machines and it is much slower than my regular POP account.

kennedy · May 20, 2009, 06:58 PM

I do not use IMAP at all. I have several POP mailboxes. I have it delete messages on the server after a day, so there's never too many messages there.

In my local folders, I have maybe 250,000 mail messages in all... organized in 200 or so mailboxes. I keep my active folders under 2000 or so messages. Some of my archival mailboxes are 10,000 or so messages. (I get 1,000 emails a month... but most are auto-filtered into appropriate dir's that I can access as needed.)

Things are a bit snappier after vacuum'ing (which reduced my index from 248MB down to 240MB).

I just had a case of a 3 minute wait when switching AWAY from a 2.4MB email to a small email. During that 3 minutes, the Activity window had just one process that said:
Getting message "<title of message I was switching AWAY from>"

Sooo, when you switch away from a message, why would it "get it"?
Or maybe it wasn't done getting it, but was showing it, and I switched to another that it couldn't get until it was done getting the big one before it? (I suggest that, because I tried to repeat it... switched to the big message, then switched right back to the little message, and the Activity window showed briefly "Stopping getting message...". Maybe sometimes the stop doesn't happen or doesn't work?)

Thanks for the help!