SPI to the SD card specifications

[pfeerick]

i have been a user of samsung evo plus 16GB for 2 years . reading the comments on this forum about samsung that mentions 32/64 GB evo plus as being a goto card i decided to try 2 32 GB cards on my various sbc units. i could detect no advantage to using 32GB over 16GB cards other than twice the storage capacity. now the fact that a 32GB card can operate at the same level as a 16GB card may be an advantage if you need the additional storage.  sd cards are, in my experience fickle and can be corrupted fairly easily. that being the case i have never had much use for over 16GB in a sbc. i'll stick with using my 32GB in cameras.

I'm seeing conflicting information on that atm. A post from 2016 which I would rely on in order to say one way or the other indicates that there is very little different between a Samsung EVO+ 32 and 64GB card, and nor is there any really difference between a Samsung EVO 64GB and Samsung EVO+ 64GB card. I suspect things would be different with a A2 class card (are there any out yet?), but that's not what we're talking about. 

I seem to remember seeing a discussion with some performance numbers indicating that the Samsung EVO 32 was faster than the Samsung EVO 64, but I can't find it again. Regardless, you can see that the Samsung EVO is the best performing of the cards in this set for the all important random writes. Being a class 10 card, it's sequential speeds are excellent anyway, but its random I/O is actually far superior to even the the A1 class spec. 



Credit: tkaiser, https://forum.armbian.com/index.php?/top...rformance/