mediaanalysisd using high CPU on a Mac: what it analyses, and when it stops
mediaanalysisd scans photos and videos for faces, objects and text. It mostly works while the Mac is idle. Why it spikes, how long it lasts, and what it saves.
730 guides
Mac storage, explained.
What fills your disk, where it hides, and what is safe to remove. Every guide gives you a way to check it on your own Mac.
What is photoanalysisd on a Mac, and why does it use CPU?
photoanalysisd builds Photos' Memories and People from your library. On our Mac, with a small library, it was not running at all. When it runs and why.
What is the bird process on a Mac? iCloud Drive's sync engine, explained
bird syncs iCloud Drive. High CPU or disk use from it means a sync is running or stuck. On our Mac it sat at 0% with 6 MB. How to check and restart it.
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 nsurlsessiond on a Mac, and what is it downloading?
nsurlsessiond does background downloads and uploads for apps and macOS. High network use from it means a big transfer. How to see which app asked for it.
What is backupd on a Mac? Time Machine's process, and why it uses CPU
backupd is Time Machine. It runs as root and works hard during a backup, especially the first. At rest on our Mac it used 0% and 2 MB. What drives it up.
What is trustd on a Mac, and why is it using CPU?
trustd checks certificates for every secure connection and signed app. Two copies run. On our Mac it showed an energy impact of 1.4. When it spikes and why.
syspolicyd using high CPU on a Mac: Gatekeeper at work
syspolicyd is Gatekeeper: it checks apps and code before they run. Developers see it spike after builds. It used 0.6% to 1.4% on our Mac. What sets it off.
logd using high CPU on a Mac: finding the app that is logging too much
logd stores every log message on a Mac. When it is busy, an app is logging far too much. It used 1.4% CPU on our Mac. How to find the chatty process.
What is locationd on a Mac, and which apps are using your location?
locationd provides location to apps and macOS. It used 0.1% CPU and 10 MB on our Mac. How to see which apps asked for location, and turn it off for them.
What is cfprefsd on a Mac, and why deleting a .plist does not reset an app
cfprefsd keeps every app's preferences in memory and writes them to disk. That is why a deleted .plist can come straight back. How to reset an app properly.
opendirectoryd using high CPU on a Mac: what it looks up, and why it spikes
opendirectoryd answers every question about users, groups and sign in. On our Mac it spiked to 27% CPU for a moment, then sat at 0.3%. What makes it busy.