Energy

Measured October 22, 2026

In short: while playing, Moireloop costs about 5% of one core (0.7% of the machine) and 31 MB, measured on October 22, 2026 on a MacBook Air M1. When the desktop is hidden, the app stops.

The measurement

Measure	Value
Moireloop CPU, median	5.3% of one core, i.e. 0.66% of the machine (8 cores)
CPU, mean · 95th percentile · maximum	5.6% · 8.3% · 13.0% of one core
Memory (RSS), median	31 MB
WindowServer (the whole desktop, not only Moireloop), median	36% of one core

Conditions: MacBook Air M1 (8 cores, 8 GB), built-in 2560×1600 display, macOS 27.0.1, Moireloop 1.0, on battery (52%), animated wallpaper playing, real use (windows open, desktop partly visible). 96 samples every 2 seconds over 3 minutes, October 22, 2026, 8:48 to 8:51 pm. First pass: no "desktop hidden" condition yet, no 4K vs 1080p comparison, no dual display, no one-hour battery run; they will appear here, dated.

Pause rules

Desktop covered by a window or a full-screen app: playback stops (option "pause when the desktop is covered", on by default).
Display asleep, Mac locked, session inactive: playback stops.
On battery, below an adjustable threshold: playback stops (option "pause on battery", on by default).
Several displays: each one is handled separately.
Quit: no process is left running.

Reproduce it yourself

Open Activity Monitor, CPU tab, and watch the Moireloop row for a minute with the desktop visible; then cover the desktop with a full-screen window: the row should drop to 0.0. In Terminal, the same thing in numbers: ps -o %cpu,rss -p $(pgrep -x Moireloop), repeated every two seconds.

What these numbers do not say

Percentages are "of one core", like the ones other apps advertise; divide by the number of cores for the whole machine. Activity Monitor's "energy impact" is a unitless index, and Apple's watt estimates are not comparable between Macs: that is why we publish measurements on a named machine, with their date, rather than a promise.