SD, eMMC, SSD, NVME, USB bandwidth tests on AMD Ryzen, i.MX8, and Jetson Orin Nano

Below are some interface bandwidth tests on various systems/drives using hdparm -tT. With hdparm, my understanding is:

  • cached reads: essentially the RAM bandwidth of the host CPU – should be roughly the same for all devices
  • buffered disk reads: the read bandwidth of the disk interface. The Jeson speed divided by 4 is 388, and we got 300 on the i.MX8.

Note, the i.MX8 setup in this test had some hardware modifications to the PCI signals that were not compliant for routing the high-speed signals, so the performance may be degraded in this test. Will update this once we have the next rev.

Note, below is just a sample of one – results did vary some from run to run.


  1. Jetson NVMe speed is almost as fast as the AMD workstation
  2. NVMe read bandwidth is more than 5 times more than SSD.
  3. the i.MX8 single-lane nVME speed is less than 1/4 the speed of the 4-lane systems.
  4. the eMMC on the i.MX8 is almost as fast as the NVMe (280 vs 300).
  5. SD is quite slow compared to eMMC (70/85 vs 280).
  6. SD speeds on Jetson and i.MX8 were similar (70 vs 85).

Summary of test results:

Platform Disk Disk Read Bandwidth
AMD NVMe 1,847 MB/sec
AMD SSD 332 MB/sec
AMD Aegis NVX (USB 2.0) 38 MB/sec
AMD Aegis NVX (USB 3.0) 418 MB/sec
i.MX8 SD 85 MB/sec
i.MX8 eMMC 280 MB/sec
i.MX8 NVMe 300 MB/sec
Orin SD 70 MB/sec
Orin NVMe 1,554 MB/sec

AMD Ryzen 3900X Workstation

NVMe Samsung SSD 970 EVO 500GB

 Timing cached reads:   32046 MB in  1.99 seconds = 16081.96 MB/sec
 Timing buffered disk reads: 5544 MB in  3.00 seconds = 1847.35 MB/sec


 Timing cached reads:   31542 MB in  1.99 seconds = 15834.95 MB/sec
 Timing buffered disk reads: 998 MB in  3.00 seconds = 332.61 MB/sec

i.MX8 QuadMax


 Timing cached reads:   1592 MB in  2.00 seconds = 795.83 MB/sec
 Timing buffered disk reads: 842 MB in  3.01 seconds = 280.14 MB/sec


 Timing cached reads:   1620 MB in  2.00 seconds = 810.12 MB/sec
 Timing buffered disk reads: 256 MB in  3.01 seconds =  85.06 MB/sec

NVMe (1 lane) Samsung 970 EVOPlus 1TB

 Timing cached reads:   1582 MB in  2.00 seconds = 790.66 MB/sec
 Timing buffered disk reads: 900 MB in  3.00 seconds = 299.57 MB/sec

Jetson Orin Nano


 Timing cached reads:   6080 MB in  2.00 seconds = 3043.07 MB/sec
 Timing buffered disk reads: 212 MB in  3.03 seconds =  70.04 MB/sec

NVMe (4 lane) Samsung 970 EVOPlus 1TB

 Timing cached reads:   7836 MB in  2.00 seconds = 3922.64 MB/sec
 Timing buffered disk reads: 4664 MB in  3.00 seconds = 1553.92 MB/sec

This is good insight. Do we have NVMe working on MX8 now ?

Yes, as of today :grinning:, it is working.

nice. Was it a missing connection on board or a misconfigured DT issue ?

Swapped Rx and Tx signals on the PCI lane – another :horse:

1 Like

I recently got a 4TB NVME with a PCI adapter card, as my AMD Ryzen 3900X motherboard only has an NVME M.2 slot.

The results are kind of disappointing compared to the on-board slot:

On-board slot

NVMe Samsung SSD 970 EVO 500GB

[cbrake@ceres yoe-distro]$ sudo hdparm -tT /dev/nvme0n1

 Timing cached reads:   34112 MB in  1.99 seconds = 17121.38 MB/sec
 Timing buffered disk reads: 6106 MB in  3.00 seconds = 2034.60 MB/sec

PCI Riser slot

Crucial P3 Plus 4TB PCIe Gen4 3D NAND NVMe M.2 SSD

[cbrake@ceres yoe-distro]$ sudo hdparm -tT /dev/nvme1n1

 Timing cached reads:   34618 MB in  1.99 seconds = 17378.62 MB/sec
 Timing buffered disk reads: 1546 MB in  3.00 seconds = 515.00 MB/sec

I’m not sure what the difference is as the PCI adapter card should support 4 lanes. The difference could be the drive – guess I need to try it with an EVO drive. It is still a little faster than the on-board M.2 SSD slot.

On the i.MX8 platform with a single PCI lane, I did some tests transferring and writing large datasets using Syncthing. Syncthing was super easy to install – just wget the release and run it. Then I synchronized some large data collections to various devices.

  • NVMe: 110MiB/s (it appears a NVMe drive can pretty much keep up with writing data streaming over GiB Ethernet.
  • eMMC: the rate went up and down quite a bit, but probably averaged around 25MiB/s.
  • SD: 15MiB/s

NVMe is a good option in embedded systems if you need fast/large storage. Adding to your board is not that hard – requires a clock chip and two differential pairs for the PCIe Rx/Tx signals. PCIe is a very interesting signaling standard as the data clock is embedded in the data signals, so other than signals in each diff pair there are no hard requirements in length matching the clock and data lines.

my hunch is its more of brand of SSD

Just tried an Apricorn 500GB Aegis NVX Encrypted USB hard drive (required for a project) on USB 2.0 and USB 3.0. The buffered disk reads are:

  • USB2: 37.88 MB/sec, 303 Mbps (theoretical max 480 Mbps)
  • USB3: 417.67 MB/sec, 3,341Mbps (theoretical max 5 Gbps)

Depending on the motherboard, it may not be running using four lanes as you may expect. I have seen slots closer to the bottom (furthest from CPU) run at 2x or even 1x speeds even though they are 16x PCIe slots.

hi @Andrewpaskiewicz --welcome to the TMPDIR community!

Thanks for the note on differences in PCI slots – that is good to know and I’ll see if I can move it closer to the CPU next time I have the case apart.