Mavericks: Mail uses 100% cpu

I my case it had nothing to do with a GMail account or whatever (I don't have a GMail account in Apple Mail). Instead it was an installation of GPG Tools (I tried GPG Mail plugin v2.1 and v2.5b6)!

I had the problem, that the CPU load was very high (starting around 30% and going up to 92–95%) when composing a new message (even if the message was only opened without editing). When I closed the window, CPU load went down immediately. The problem started after updateing from 10.8.5 to 10.9.5 just yesterday!!! (Yes, I am late ...) I had no problems at all in 10.8.5.

I found no solution so far other than a deinstallation of GPG Tools. I hope it is not a mix of problems (GPS Tools and one of the other possible or impossible reasons for this problem like mail index, bad fonts or whatever – I also have no abnormal large Accounts.plist file) .... I will try to find it out with the GPG Tools Support ...

For more information see these threads in GPG Tools Support:

http://support.gpgtools.org/discussions/problems/14580-mail-71-in-mavericks-cpu- load-while-composing-an-email-with-installed-gpg-plug-in

http://support.gpgtools.org/discussions/problems/36867-os-x-1095-and-apple-mail- 73-in-mavericks-high-cpu-load-while-composing-an-email-with-installed-gpg-plug-i n

Best Regards,

Patrick

Not to throw a wrench into this but I have a hunch that iCloud has a lot to do with it. Stripped it down to sync nothing but calendar and contacts and Mail seems to be running smoothly with Gmail IMAP and nothing else. My RAM is steady with no gradual loss over time with Mail open while I work.

I have tracked down my exact cause for this problem without having to a re-install.

Settings>Internet Accounts>

Select all (I have four) “Google” accounts installed and uncheck “Contacts”

Immediate cessation of activity from these files. You can keep Mail and Calendars but not contacts...

I am a software engineer who spent weeks on this. I got here with the slow destroy method (delete an application and see if things get better) after reinstalling the OS twice and also doing a PRAM reset. Apple support gave up and told me to format my drive and start over with a clean OS and transfer only my data. As a developer that would have been days and I would have lost some stuff forever so I decided to go backward instead. I used brew to install app-cleaner and slowly deleted applications while watching Activity Monitor..

Good luck

Yes thanx now the mail app looks normal a few % cpu

/Björn

Thank you! I restarted Mail.app with the shift key held down, and it went from 100% CPU all the time to less than 1%!

I'm getting quite fed up with this bug. It's to do with the network and mail getting into some loop or other.

I make extensive use of a VPN to connect to the company email system. If I open mail without connecting the VPN, I'll frequently get 200% cpu as the 747 trundles down the runway for take off (i.e. the fans run flat out on the MBP). If I *connect* the VPN, then the fans go off again.

Once settled down, the CPU levels drop back to normal levels. Or as of this moment, 130%.

When the mail thing finally annoys me enough, I'll quit it - wait for the processes to die (this frequently takes 10 seconds - as shown in Activity Monitor). Then restart it. Et voilla, back to normal unless the VPN drops out.