There is a 5 GB file created in /media/virtualfilesystem. This serves as the media for an ext4 file system mounted in /home/ubuntu/StreamData. Use only this directory to write camera and enerated video streams. This is a security precaution.
All developed applications that write to local storage on Jetsons must be instructed to write to /home/ubuntu/StreamData. You're free to allocate and make subdirectories as needed. Keep in mind the 5GB total limit, and copy any useful/necessary data to your own storage devices as soon as you can.