cRIO CPU utilization - running from project vs real-time executable

[Corey.Rotunno]

Hello, 
  I have an application that I've been working on that's deployed to a cRIO target. So far, I've been running the code mostly by deploying my project directly. Today however I built an rtexe. 

  My issue is that when I run my Main.vi from the project directly, my CPU usage is healthy, ~10%. When my real-time executable runs however, CPU usage is >95%. I am operating in hybrid mode, with two serial modules using the ni-serial scan engine support. Other than that, nothing too out of the ordinary.

Does anyone have any insight into what might cause an RT EXE to hog so much more CPU vs. the same VI running in project mode?

  

[Corey.Rotunno · Accepted solution]

False alarm. As previously mentioned, I am running in hybrid mode. One of my modules, an NI9213, is running in "Real-Time NI-DAQmx" mode. When running from my project, the bitfile was always previously running so no problem. When I ran application as a startup-vi though, the DAQmx read loop did not wait long enough for the FPGA bitfile reference to open and start running. This cause an error which caused a run-away loop around my DAQmx read.