Nano 2gb JetPack 4.5 irq/74-tegradc Process

Just upgraded Jetson Nano 2gb to the new JetPack 4.5 release. We are running without the lightdm or other display manager. A “top” with none of our programs running, the top process is “irq/74-tegradc.” What is that interrupt and what is it doing?

The software we are developing is using OpenCV to run several detectors on an input video stream. Two of the detectors run on the graphics processor using CUDA. The Nano 4gb version running the same program is very responsive to terminal commands. The Nano 2gb terminal is totally unresponsive running the same program. The nvzram had to be disabled to get the programs to run and only the 4gb swapfile is being used. Is that irq/74-tegradc process aggravating the memory swap and terminal response issues.


tegradc means display controller. Even if there is no display connected on it, display driver is still needed to be running to make sure it can run hotplug case.

Are you sure this one is consuming memory? I don’t see any of activity on my side.

I am not sure exactly what is causing the system to become unresponsive. When the two processes that are using CUDA begin to detect objects, the terminal becomes extremely slow or doesn’t react at all. If one of the CUDA processes are killed, the system is back to normal. CPU usage never gets above 80% so the issue isn’t processing power.