$ lsusb Bus 001 Device 024: ID 13fe:3800 Kingston Technology Company Inc.
# The device can access 12 12 MB erase blocks:
arnd@klappe2:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[3 * 8192] --erasesize=$[3 * 4096 * 1024] --open-au-nr=20 12MiB 12.9M/s 6MiB 10.8M/s 3MiB 7.49M/s 1.5MiB 4.66M/s ^C arnd@klappe2:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[3 * 8192] --erasesize=$[3 * 4096 * 1024] --open-au-nr=12 12MiB 10.2M/s 6MiB 13.8M/s 3MiB 13.5M/s 1.5MiB 13.2M/s 768KiB 13.1M/s 384KiB 12.8M/s 192KiB 12.7M/s 96KiB 15.3M/s ^C arnd@klappe2:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[3 * 8192] --erasesize=$[3 * 4096 * 1024] --open-au-nr=16 12MiB 14.2M/s 6MiB 11M/s 3MiB 7.64M/s 1.5MiB 4.78M/s 768KiB 2.69M/s 384KiB 1.45M/s 192KiB 767K/s ^C arnd@klappe2:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[3 * 8192] --erasesize=$[3 * 4096 * 1024] --open-au-nr=13 12MiB 12.9M/s 6MiB 11.5M/s 3MiB 8.35M/s 1.5MiB 5.13M/s 768KiB 2.89M/s 384KiB 1.54M/s 192KiB 758K/s 96KiB 732K/s ^C arnd@klappe2:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[3 * 8192] --erasesize=$[3 * 4096 * 1024] --open-au-nr=12 [sudo] password for arnd: 12MiB 16.2M/s 6MiB 13.2M/s 3MiB 13M/s 1.5MiB 13M/s 768KiB 13.1M/s 384KiB 12.5M/s 192KiB 12.5M/s 96KiB 14.9M/s 48KiB 9.55M/s
# This also works with 8 MB units (properly aligned to 24 MB by modifying flashbench): $ sudo ./flashbench /dev/sdc --open-au --blocksize=$[2 * 8192] --erasesize=$[ 2 * 4096 * 1024] --open-au-nr=12 8MiB 12.8M/s 4MiB 11.8M/s 2MiB 10.3M/s 1MiB 16.6M/s 512KiB 17M/s 256KiB 15.6M/s 128KiB 13.6M/s 64KiB 18.4M/s 32KiB 11.9M/s 16KiB 3.41M/s
arnd@klappe2:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[2 * 8192] --erasesize=$[ 2 * 4096 * 1024] --open-au-nr=13 8MiB 16.4M/s 4MiB 16.6M/s 2MiB 14.4M/s 1MiB 13.1M/s 512KiB 10.4M/s 256KiB 6.55M/s 128KiB 3.87M/s ^C
$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[2 * 8192] --erasesize=$[4 * 4096 * 1024] --open-au-nr=12 16MiB 13.4M/s 8MiB 13.4M/s 4MiB 11.6M/s 2MiB 14.4M/s 1MiB 16.4M/s 512KiB 16.8M/s 256KiB 15M/s
The results are still not conlusive, especially after doing more tests with --random. Will have to revisit.