What is cloudd on a Mac, and why are there two of them?
cloudd syncs app data through CloudKit: Notes, Reminders, Safari and many App Store apps. Two copies run, one for you and one for the system. When it uses CPU.
What is cloudd?
cloudd is the CloudKit daemon. Apps that keep data in iCloud, Apple's own and many from the App Store, sync it through cloudd. iCloud Drive files go through bird instead; cloudd carries app data such as notes, reminders, bookmarks and game saves.
It lives in /System/Library/PrivateFrameworks/CloudKitDaemon.framework.
| Copy on our Mac | Runs as | CPU | Memory | Running for |
|---|---|---|---|---|
| One | our user | 0.0% | 6 MB | since login, 30 hours |
| Two | root | 0.0% | 2 MB | 34 minutes |
Why are there two cloudd processes?
One syncs your apps' data; the other serves system services that run outside your account. Both are normal.
Why is cloudd using CPU?
An app is syncing a lot: a first sync on a new Mac, a large Notes or Photos change, a game uploading saves. It settles once the sync ends. If it stays busy for hours, quitting the app that is syncing, or signing out of iCloud and in again as a last resort, resets it. What iCloud keeps on disk is in iCloud storage full vs Mac storage.
See it live
Free Mac's System tab ranks every process by processor use and energy impact, once a second, and marks the ones macOS will not let you quit as protected. See also bird and nsurlsessiond.
Related: nsurlsessiond and backupd.
Common questions
What is cloudd on a Mac?
The CloudKit daemon. It syncs app data, such as notes, reminders and bookmarks, through iCloud.
Why are there two cloudd processes?
One runs for you and one for system services. On our Mac one ran as our user and one as root.
Is cloudd the same as bird?
No. bird syncs iCloud Drive files; cloudd syncs app data through CloudKit.