Mac process glossary
These are the background processes you're most likely to see near the top of Activity Monitor's CPU list on a Mac. Each page explains what the process does, why it gets busy, how to calm it down with tools built into macOS, and whether it's safe to quit.
Core macOS
The processes that run macOS itself.
- kernel_taskThe core of macOS.
- WindowServerDraws everything on your Mac's screen.
- launchdStarts and manages every process on your Mac.
- logdCollects log messages for macOS.
- syspolicydThe macOS service that checks apps are safe to open (Gatekeeper).
- trustdChecks security certificates for websites and apps on your Mac.
- distnotedPasses notifications between apps and macOS services.
Spotlight, Photos and media
Indexing and analysis that runs after imports and updates.
- mds_storesManages your Mac's Spotlight search index.
- mdworker_sharedProcesses read your files for Spotlight search.
- photoanalysisdAnalyses your Photos library for people, scenes and Memories.
- mediaanalysisdAnalyses photos and videos for Live Text, Visual Look Up and search.
- corespotlightdIndexes app content like Mail, Notes and Messages for Spotlight.
iCloud, downloads and backups
Syncing, downloading and backing up in the background.
- clouddSyncs iCloud data for your Mac's apps.
- birdThe background service for iCloud Drive.
- fileproviderdManages cloud storage folders like iCloud Drive, Dropbox, Google Drive and OneDrive on your Mac.
- nsurlsessiondHandles background downloads and uploads on your Mac.
- softwareupdatedChecks for and prepares macOS updates.
- backupdRuns Time Machine backups on your Mac.
Finder, Dock and input
The parts of macOS you click on, and your keyboard and mouse.
Browsers and audio
Helpers that belong to apps you're using.