CalNCService uses 100% CPU for extended periods of time
Number:rdar://35464009 Date Originated:10-Nov-2017 10:25 AM
Status:Open Resolved:
Product:macOS + SDK Product Version:10.13.2 Beta (17C67b)
Classification:Performance Reproducible:Sometimes
Once every while I notice my fans kicking in, and checking activity I see CalNCService using high CPU percentage.

Steps to Reproduce:
I don’t know how to reproduce it.

Expected Results:
CPU should not stay that active.

Actual Results:
I didn’t time it, but I’d estimate it stays active more than 10 minutes - 1h or so.

10.13.2 Beta (17C67b)

I have one iCloud, two google, one facebook account, each with calendars activated.


Apple Developer Relations

Thanks, we are working on the new information you provided. We appreciate your help!

By at Feb. 2, 2018, 11:34 a.m. (reply...)

Hannes Oud

I'm sorry, I mis-spellt it with two L accidentally. It is CalNCService and lives at /System/Library/PrivateFrameworks/CalendarNotification.framework/Versions/A/XPCServices/CalNCService.xpc/Contents/MacOS/CalNCService

By at Feb. 2, 2018, 11:34 a.m. (reply...)

Apple Developer Relations

We don't have enough information to investigate this issue.

I have never heard of CallNCService. I also don't think we own this service.

Please update your bug report to let us know if this is still an issue for you, and provide any additional information.

By at Feb. 2, 2018, 11:34 a.m. (reply...)

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