Hi,
in addition to some research regarding a few quality SD cards I wanted to ask our users to contribute to some collective benchmarking.
In case you bought Samsung, SanDisk, Toshiba or Transcend SD cards within the last few months, have a A20 device and are able to test the card in question, please use this A20 Armbian 5.07 image (vanilla kernel, performance governor, no user creation), burn the image on the card, connect board to network, start it and do the following at least twice
iozone -e -I -a -s 100M -r 4k -r 16k -r 512k -r 1024k -r 16384k -i 0 -i 1 -i 2
Please be aware that some cards seem to need some time for auto calibration when being first used so please do the test at least two times and in case results improve repeat the test until results seem to be stable (please see the test linked above for my experiences with a few Samsung cards that needed 4 test runs and then some performance values were twice as good than before).
When you're finished please execute 'armbianmonitor -u' to collect system information and post the support URL armbianmonitor provides, your test results and description of your board and the tested card in this thread.
I'm especially interested in results of cards with different capacity so in case you've for example two SanDisk Extreme Plus (one with 8 and another with 32 GB) then results from both cards are interesting since performance might improve with higher capacity cards.