Q: CalendarAgent process is out of control - delegation may be causing problems?

I was able to get this to stop.  Go to:

• System Preferences
• Notifications

Click the "Calendar" entry on the left.  Un-Check everything on the right.  The entry moves to the bottom (or below the line).  After that, my CPU went straight down to a normal percentage, system temp dropped, etc.

This is a *bug*.  Let's hope a fix comes out so we can enable notifications again!

Hope this helps.

-Steve

@shornby:

That did not do it for me. I still get spiking CPU on the calendar agent, even with notifications turned off. I did not have this problem until our company went to Office365, Exchange-based calendar in the cloud. So many issues for Mac users, and it would seem that M$ and Apple point fingers at each other.8/13/12 8:39:52.863 AM

I see many of these in my logfile:

WindowServer[603]: CGXDisableUpdate: UI updates were forcibly disabled by application "Microsoft Office Reminders" for over 1.00 seconds. Server has re-enabled them.

I am having the same problem, but only when I have my Exchange calendars turned on. I have no problem with my iCloud account. I have no Google calendars.

I came up with an extreme solution: disable it entirely.

1 Startup in safe mode.

2 Move/copy /System/Library/LaunchAgents/com.apple.CalendarAgent.plist to /System

3 Delete /System/Library/LaunchAgents/com.apple.CalendarAgent.plist and reboot

No more CalendarAent process.  I did the same thing for com.apple.imagent.plist (Messages) and it worked too.

This didn't speed up my boot or shutdown time, but no more process hogging either.

I have the same problem with iCal and Exchange since installing Mountain Lion.

iCal runs like a dog, hogs CPU and is unresponsive.

Can't add or delete accounts or Calendar events.

Looks like a bug to me, Apple.

When will we get an Acknowledgement/Update/Resolution?

I treied this and it worked for me

i mean i deleted the calendar agent as suggested by saytheenay and rebooted and its fine. i will reinstate the file when they get around to providing a fix

You might try logging in to your Exchange webmail interface and dismissing all reminders.

Even though I had been dismissing reminders from my various devices, Exchange webmail presented me with hundreds of reminders from the past year or so. After dismissing all of them, iCal sync'd quickly and the CalendarAgent is behaving "normally."

I have 10.8.1 but the same problem. No syndication, no Exchange, tried the unchecking notifications. Really strangles my iMac. May be connected to my severe sync problems with my iCalendars after clean install of Mountain Lion?

Regards

sorry, not "No syndication, ", but No delegation.

Funny thing I also experience active applications that are not visible with alt-tab or on the dock??

I have been trying a lot of suolutions since i got this problem, but this one solved it. My calendaragent appeared to use 100% of the CPU, with lots of threads and 3.5 Gb or memory, but after this fix it got down to about 300 Mb and 12-15%. I did delete everything about calendar in thos folders though. And restarted in between the stop and start of canendar sync.

Regards

http://robert.accettura.com/blog/2012/08/19/how-to-stop-calendaragent-from-eatin g-cpu/

How To Stop CalendarAgent From Eating CPU

Recently ran into an issue with Calendar causing a huge CPU spike. Checking the system.log I noticed the following repeatedly in my log:

CalendarAgent is essentially Calendar’s backend (that’s how it’s also able to power the notification center). The best resolution I’ve found is to completely clear out the calendar and recreate it. Process I used was as follows:

1. Remove the Calendar from “Mail, Contacts & Calendars” pref panel (just uncheck from the account). Then go into Calendar and make sure the account is removed. If it’s not, remove it.
2. Delete ~/Library/Calendars/
3. Delete ~/Library/Preferences/com.apple.iCal.plist
4. Go back into the “Mail, Contacts & Calendars” pref panel, put the calendar back. Give it some time to download.

That seems to have worked for me.

This entry was posted in Apple and tagged calendar, os x 10.8.

and I also deleted the iCal items in the personal Library/Caches folder

I got this problem after clean install of ML. By accident I found I had 25 000 iCal events called "dummy", all on  Jan 1st 1970. After trying to delete them in iCal, with truckloads of spinning beach balls and dozens of Forced quits, I had a look inside the ics file, and this is how they look:

BEGIN:VEVENT

CREATED:20120824T174009Z

UID:E67E4327-8746-4079-9D9E-31FA4DC71A16

DTEND;TZID=Europe/Oslo:19700101T020000

TRANSP:OPAQUE

SUMMARY:dummy

DTSTART;TZID=Europe/Oslo:19700101T010000

DTSTAMP:20120824T174009Z

SEQUENCE:1

BEGIN:VALARM

X-WR-ALARMUID:92778ECD-7357-42EC-9479-90A207D563E2

UID:92778ECD-7357-42EC-9479-90A207D563E2

TRIGGER:-PT5M

X-APPLE-DEFAULT-ALARM:TRUE

ATTACH;VALUE=URI:Basso

ACTION:AUDIO

END:VALARM

END:VEVENT

I tried to find a way to search and replace, but gave up. In the end I just copied all events from this and next year to a new calendar en deleted the old one. It shrank from 19 Mb to 585 kb. Now it syncs fine again. Regards

I have the same problem with Exchange delegate calendars in Calendar, as does a colleague of mine - Calendar Agent actually says it's using 200% of the CPU - quite remarkable - and I get the system memory error. When its use drops down, the error goes away. I used iCal Cleaner and also checked for dummy events (none) as mentioned in another post, and didn't help. The only way I can reliably get rid of the problem is to remove the delegated calendars, which is a pain. I can go to Outlook 2010 via Parallels or Mac Outlook 2011, but that seems like a lousy answer. Anyone else have a better one, and has anyone heard from Apple?