Flash Card Testing

Some oneliners to test flash card devices such as SD Cards.

Testing cards with f3

Note: These are just handy oneliners, it might be a good idea to read the documentation at least once if you never used f3 before.

• Installation:

sudo apt install f3

• Capacity test:

sudo f3probe --destructive --time-ops /dev/sdx

• Performance and file corruption test:

sudo mount -o user,uid=someuser,gid=someuser /dev/sdx1 /some/where
f3write /media/stuff
f3read /media/stuff

Speed benchmarking with IOzone

Note: speed benchmarking depends on a lot of factors, not just the card itself. For instance, different SD Card USB adapters can be several times faster or slower than others with the same SD card. So for most accurate result and/or testing different settings, best is to run iozone on the final hardware where the card will be used, if possible.

• Installation:

sudo apt install iozone3

• Run a test on 100MB big file with chunks of 4K, 512K, and 16M length. Depending on the usage you might be more interested in one or other result. For an active system partition or a storage with lots of small files, 4K read/write, both sequential and random are the important values to look at.

iozone -e -I -a -s 100M -r 4k -r 512k -r 16M -i 0 -i 1 -i 2 -f /some/where/100M