Re: Forgotten memories
Standard SD cards will fail eventually if they do not have global or static wear levelling. If you are putting standard SD card into product you can not easily get to and replace you will be in a world of pain. There are techniques you can use like read into ram then never write which will make a standard SD card last a long time ( based on number of reboots). You could maybe use SPI flash for write storage instead with read and write disturb aware file-system or just use NOR flash with it’s slow erase time.
If you are gong to use a standard SD card then chose one that has android run support A1 or A2 as the flash endurance will make it last longer (like Sandisk).
So the way SD cards fail is that with read disturb multiple reads cause adjacent flash cells levels become harder to differentiate between a one or zero then you get bit flips on reads. These bit flips cause invalid files and file-systems, this makes your PI a bit flaky. If you reformat the SD card the it will be fine but the fact the pi can’t boot makes this difficult to solve remotely. If you are going to put PI in the field running from SD card make sure it has global wear levelling SD card as this is the only thing that can stop read disturb issues, they are expensive for a reason!