What is powerd on a Mac, and why does it say it is preventing sleep?
powerd manages sleep, wake and power settings. On our Mac pmset said sleep was prevented by powerd, which only meant the screen was on. How to read it.
What is powerd?
powerd is the power management daemon: it applies the settings you see in Battery and with pmset, decides when to sleep and wake, and keeps the record of power assertions apps make. It lives at /System/Library/CoreServices/powerd.bundle/powerd and runs as root. Ours used 4 to 5 MB and no CPU.
Why does it say sleep is prevented by powerd?
Because powerd holds an assertion of its own while the display is on, and lists itself among the reasons. On our Mac pmset -g assertions showed:
pid 343(powerd): PreventUserIdleSystemSleep named: "Powerd - Prevent sleep while display is on"That is normal and goes away when the display sleeps. If the Mac still never sleeps, the other names in that list are the cause; see what is preventing your Mac from sleeping.
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 pmset sleep settings and caffeinate.
Related: energy impact mean and MacBook battery drains overnight while asleep.
Common questions
What is powerd on a Mac?
The macOS power management daemon. It applies sleep and power settings and tracks what keeps the Mac awake.
Why does my Mac say sleep prevented by powerd?
powerd keeps the Mac awake while the display is on. It is normal and ends when the display sleeps.
Can I quit powerd?
No. It runs as root and macOS needs it to sleep and wake.