Issue Description: For ROS2 bagfile recording, I’ve tried multiple SSDs and multiple setups.
First, my M.2 NVME SSD has 2000MB/s write speed on the spec sheet.
Connected to the USB 3.2 port with a Thunderbolt cable, and checked if the USB version is detected correctly as 3.2 in Tegra Ubuntu.
Afterwards, changed the USB setting on Tegra by following the instructions in the high-throughput data recording manual.
Finally, I compared the writing speed using the dd command, and my regular Ubuntu shows 1.8GB/s write speed, and Tegra on Orin showed 750MB/s. I’m guessing it is because of the missing “UAS” USB driver in the Tegra kernel, but still, I’m looking for how to reach the maximum write speed the SSD has on the spec sheet.
If that’s the case, your SSD can do ~2 GB/s on PCIe, but when you connect it through a USB 3.2 → NVMe enclosure, the USB interface becomes the bottleneck. On DRIVE OS the USB ports typically run at USB 3.2 Gen 2 (10 Gbps), which gives ~700–900 MB/s.
Also note that DRIVE OS does not include the UAS driver, so the device runs in BOT mode, which further reduces throughput. This is expected behavior on DRIVE OS.
The 1.8 GB/s result you see on regular Ubuntu is likely due to caching unless you use oflag=direct.
If you need full ~2 GB/s write speed for ROS2 bagfiles, try a native PCIe/NVMe slot, not through USB because it will never reach the SSD’s spec sheet speed.
If you want, share the lsusb -t output and your dd command to confirm the exact mode your enclosure is running in.