I gathered all my flash based memory devices (USB flash memory sticks and SHDC cards) and wanted to see how do they compare to each other.
Quick google search revealed that dd tool could be used for benchmarking so that is what I used. Have you done benchamrs some other way? Please share your method.
Be really, really careful if you choose do to write test, because that will ERASE your existing data so test write speed only on EMPTY flash memory devices. Also triple check which device is your flash memory device. Simple typo could render your data partition unusable!
I didn’t want to write on the first 1GB of flash memory because that part is probably most often used, I know there are some wear-leveling chips that should take care of that but you can use skip parameter if you wish to be safe. To prefent mesuring your cache performance but actual device performance use iflag and oflag options.
read speed benchmark:
$ sudo dd if=/dev/sdX1 of=/dev/zero bs=1M count=400 iflag=direct
write speed benchmark :
$ sudo dd if=/dev/zero of=/dev/sdX1 bs=1M count=400 skip=1000 oflag=direct
|Adata 8GB class 10
|Apacer 4GB class 4
|LG 2GB class unknown
|USB memory stick
|2GB Transceng VF V90
|4GB Kingston DT 108
|8GB Kingston DT 2.0
|8GB Kingston DT SE9
|4GB Red USB
|8GB Silicon Power SP 810