RSS Bot Posted September 4, 2023 Posted September 4, 2023 Description This problem was first reported by a user on Armbian forum affecting Orange Pi Win and Orange Pi Prime with 6.1 kernel. The problem was when running iperf3 for network testing, it reported extremely low speed in the range of 40Mbps instead of 900Mbps that was shown on Debian kernel. It was also observed on multiple other devices during testing of 6.5 including Orange Pi Zero Plus by @schwar3kat and Pine A64+ by @PanderMusubi. Legacy kernel performed a bit better giving 400+ Mbps speed. Running something like htop or watch -n 1 echo in parallel seemed to resolve the issue. I was able to narrow it down to sun8i-a33-mbus driver which is dram frequency scaling driver for H5 and A64. It claims to support a33 to H3 as well, but I don't see the device tree compatible string for them in the driver code. Manually changing governor or min_freq in sysfs seems to get the speed back up. But when I tried changing the code ( it was just one variable value), the higher dram speed on reboot didn't solved the issue. Hence as a workaround, I am disabling this driver to bring back the speed. Disabling this driver also speeds up rendering on uart. Previously, when running neofetch it used to take about 5 seconds to render on my Orange Pi Prime, but now it renders in a fraction of second. After disabling this driver, the speed shown by iperf3 on legacy kernel is also up from previously reported 400Mbps to 900Mbps. Jira reference number AR-1833 How Has This Been Tested? Please describe the tests that you ran to verify your changes. Please also note any relevant details for your test configuration. [X] Tested on Orange Pi Prime (sun50i H5) Checklist: [ ] My code follows the style guidelines of this project [ ] I have performed a self-review of my own code [ ] I have commented my code, particularly in hard-to-understand areas [ ] I have made corresponding changes to the documentation [X] My changes generate no new warnings [ ] Any dependent changes have been merged and published in downstream modules View the full article
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