Rock 5B experience
Performance of A76 cores of RK3588 is 2 to 3 times higher than the older A72 cores of RK3399 and RK3588 also embeds the same A55 efficient cores of RK3568. So Rock 5B is a much more powerful board that offers larger PCIe bandwidth and also a more powerful NPU compared to Rock 3A. In short, we have much more power and the maximum bandwidth for our two SATA controllers.
Recently, QNAP released its 6-bay NAS surveillance TS-AI642 based on RK3588, and this is exactly what we have here in hands in terms of hardware, although I saw no information on the SATA controller or its RAID level support yet on this dedicated model.
Here, it is not possible to firmly fix the Penta hat (or the ribbon cable) to the board while the ASM1166-based module can be directly screwed at the back of the board, so I logically decided to only benchmark the latter. Nevertheless, hosting the Rock 5B in a case is not that easy since both sides of the board require clearance, on top side for the heatsink, on bottom side for the SATA cables!
System is the official Radxa Debian 11 CLI image for Rock 5B with kernel 5.10. The ASM1166 NVME module was recognized flawlessly out-of-the-box and RAID volumes are created and managed in OVM, installed by means of the script on this Debian version.
Tests are run with the SSD and the three HDDs connected on the SATA board:
RAID5 (3xHDD) → SSD: 283 MB/s (with some I/O errors)
SSD → RAID5 (3xHDD): 260 MB/s
RAID0 (3xHDD) → SSD: 208 MB/s (abnormal - too many I/O errors)
SSD → RAID0 (3xHDD): 480 MB/s
Once again, I noticed many kernel I/O errors in transfers from RAID0 to SSD, destroying the chances to get representative numbers. It was confirmed in RAID5 (initially 168 MB/s), so I decided to change some cables and results were significantly improved. However, in the other direction, write performance to RAID5 (260 MB/s) is almost the same as on my main i3-12100 x86 solution (275 MB/s) using the same three HDDs and, in case of RAID0, we almost reach the SATA 6 Gbps limit, which is more than satisfying.
CPU bound is reached in my RAID write tests, but not in read tests.