Jetson Orin NX giving lower fps than Orin Nano

[markaajan]

Hi,
I am trying to set up two Zed2i cameras running on a Jetson. We were initially using the Jetson Orin which gave us a pointcloud at around 7Hz with Object detection (person accurate only) running in neural mode. Since we were running out of memory, we then tried the Orin NX but this gave us only around 4 fps. Both Jetsons are running at their respective max powers. Any idea what could be causing this discrepancy as I believe the Orin NX should perform better. I am running ROS2 Foxy with SDK 4.0.8. The setups are identical and I am using the same configuration file on both. They are running Jetson Linux 35.4.1.

[Myzhar]

Hi @markaajan
Welcome to the StereoLabs community.

Can you please specify how do you measure the FPS?

[markaajan]

I am using the “ros2 topic hz” function to measure the point cloud message rate on both.

[Myzhar]

Point cloud subscribing takes a lot of resources if DDS is not correctly tuned.

I recommend using rqt and the runtime monitor plugin to verify the real frequency of running of the ZED nodes.

To tune the DDS and improve message publishing I recommend following these guides:

• DDS tuning information — ROS 2 Documentation: Humble documentation
• Additional settings for developers - Autoware Documentation
• 15.3. Large Data Rates — Fast DDS 2.13.1 documentation
• Unlocking the potential of Fast DDS middleware [community-contributed] — ROS 2 Documentation: Galactic documentation

[markaajan]

I checked using rqt and am getting similar results with the topic monitor plugin. Around 4.5 Hz for both the pointcloud topics on Orin NX and around 7-7.5 Hz on the Orin Nano.

I will check out the DDS tuning soon and get back. Thank you for the references.

[markaajan]

So i just found that there is a MAXN power setting which was higher than 25W. Changing that now gives around double the frame rate on Xavier NX. Thank you once again.