Changing the priority of apps and system processes on macOS helps your computer allocate resources where you need them most. This guide walks you through safe, official ways to adjust priority on Mac so your workflow stays smooth.
Use these steps to manage performance for demanding tasks like video editing, gaming, or running multiple virtual machines.
| Priority Level | Description | Impact on System | When to Use |
|---|---|---|---|
| Low | Background maintenance tasks | Minimal CPU and memory usage | Idle or non-urgent syncs |
| Normal | Standard foreground apps | Balanced resource allocation | Regular browsing and document work |
| High | Active professional applications | Increased CPU scheduling preference | Video rendering or compiling code |
| Very High | Time-critical real-time tasks | Aggressive processor access | Performance testing or low-latency audio |
How to View Current Process Priority
Before changing anything, it helps to see what is already running and how the system is prioritizing tasks.
Using Activity Monitor
Activity Monitor provides a visual overview of CPU, memory, and energy impact for every process.
Using Terminal Commands
The top and ps commands let you inspect numeric priority values such as nice scores and thread scheduling policies.
Adjust Priority with Nice Values
The nice value controls CPU scheduling priority for processes in Terminal, where lower numbers mean higher priority.
Setting a Nice Value on Launch
Use nice -n
Renicing an Existing Process
The renice command changes the priority of a running process using its process ID, useful for tuning performance on the fly.
Elevate Priority with sudo and Terminal
To raise a process above normal scheduling priority, you need sudo access and a clear understanding of the risks.
Using sudo and chrt for Real-Time Policies
The chrt command with sudo lets you assign real-time scheduling policies, giving a process strict control over CPU time.
Security Considerations
Higher priority can make the system less responsive for other users, so apply elevated priority only when necessary and for limited sessions.
Automating Priority Tweaks with Scripts
For repetitive tasks, shell scripts and launch agents can set priority automatically while maintaining consistency.
Creating a Startup Script
Place a small shell script in your launch agents folder to apply nice or chrt values when specific applications start.
Monitoring and Logging
Add logging to your scripts so you can review how priority changes affect system behavior over time.
Best Practices for Managing Priority on Mac
- Start with normal priority for everyday apps to preserve system responsiveness
- Use high or very high priority only for short, controlled tasks
- Monitor system load before and after changing priority
- Automate repeated adjustments with launch agents and logging
- Use sudo carefully and prefer non-root methods when possible
FAQ
Reader questions
Will changing priority slow down other apps on my Mac?
Yes, giving one process very high priority can reduce performance for other apps, so use elevated levels sparingly.
Can I change priority for apps with graphical buttons?
macOS does not provide direct GUI controls for priority; you must use Terminal or scripts to adjust nice or scheduling values.
Do priority changes survive a restart on macOS?
No, most adjustments are temporary and must be reapplied after each reboot unless automated with launch agents.
Is it safe to use sudo with chrt or renice?
Yes, it is safe when you understand the impact, but incorrect values can make the system sluggish or unresponsive.