Warm up your MacBook (2019)

Source: Hacker News

How to Warm Up Your MacBook Quickly

You’ve been there – after a cold commute, you sit down, place your palms on the keyboard, and feel the metal drain the heat from your skin. The fastest way to warm up a laptop is to make it work hard.

Using the yes Command

The built‑in yes command can peg your CPU at 100 %:

yes > /dev/null

Running this in Terminal repeatedly sends the word yes to the null device, keeping the CPU fully occupied.

Using the stress Utility

For a more aggressive warm‑up, install and run the stress utility:

brew install stress
stress -c 6 -m 2 -t 300

• -c 6 creates 6 CPU‑stress threads (100 % each)
• -m 2 creates 2 memory‑stress threads (malloc/free)
• -t 300 runs for 300 seconds (5 minutes) to prevent overheating if you walk away.

Automating with an Alias

Add an alias to your ~/.bash_profile (or ~/.zshrc) for one‑click warming:

alias warm='stress -c 6 -m 2 -t 300'

Now you can start the stress test simply with:

warm
# Output:
# stress: info: [65121] dispatching hogs: 6 cpu, 0 io, 2 vm, 0 hdd

Stay warm this winter!