Recommended CPU Usage for Real-Time Targets

Issue Details

I am developing my LabVIEW Real-Time application, and I notice the CPU usage is high. Which is the recommended CPU usage level for Real-Time targets?

Solution

Good practice to keep CPU usage below 75%. This benchmark allows you to:

1. Ensure tasks do not need to compete for CPU time (whenever CPU usage is 100%, tasks are waiting)
2. Leave extra room for spikes in CPU usage, such as fault conditions and error handling code.
3. Avoid possible disconnection issues.

Additional Information

The next list contains some steps you can follow to fix a high CPU usage level in your Real-Time target:

1. Refer to the document Monitoring CPU and Memory Usage on Real-Time Embedded Targets to understand how to read the CPU usage of your device.
2. Review the LabVIEW Real-Time Help document: Minimize CPU Usage (Real-Time Module)
3. Take the next additional actions if CPU usage is still too high:
   • Log warning to file
   • Notify user interface
   • Adjust loop periods and avoid running while loops without timing functions (i.e Wait (ms).vi). Learn more about Timed Loops, here: Configuring Timed Loops and Timed Loops with Frames (Real-Time, Windows)
   • Optimize code. 
   • Transfer CPU intense processing to the FPGA (if available)