I tested this card, but an older one, 2 years back: http://lists.linaro.org/pipermail/flashbench-results/2012-February/000252.ht...
This is a newer one and is different.
root@localhost:~# head /sys/block/mmcblk1/device/* 2>/dev/null | grep -v ^$ ==> /sys/block/mmcblk1/device/block <== ==> /sys/block/mmcblk1/device/cid <== 02544d5341303447113533890900d371 ==> /sys/block/mmcblk1/device/csd <== 400e00325b5900001d177f800a40008d ==> /sys/block/mmcblk1/device/date <== 03/2013 ==> /sys/block/mmcblk1/device/driver <== ==> /sys/block/mmcblk1/device/erase_size <== 512 ==> /sys/block/mmcblk1/device/fwrev <== 0x1 ==> /sys/block/mmcblk1/device/hwrev <== 0x1 ==> /sys/block/mmcblk1/device/manfid <== 0x000002 ==> /sys/block/mmcblk1/device/name <== SA04G ==> /sys/block/mmcblk1/device/oemid <== 0x544d ==> /sys/block/mmcblk1/device/power <== ==> /sys/block/mmcblk1/device/preferred_erase_size <== 4194304 ==> /sys/block/mmcblk1/device/scr <== 0235800001000000 ==> /sys/block/mmcblk1/device/serial <== 0x35338909 ==> /sys/block/mmcblk1/device/subsystem <== ==> /sys/block/mmcblk1/device/type <== SD ==> /sys/block/mmcblk1/device/uevent <== DRIVER=mmcblk MMC_TYPE=SD MMC_NAME=SA04G MODALIAS=mmc:block
root@localhost:~/flashbench# fdisk -l /dev/mmcblk1
Disk /dev/mmcblk1: 3904 MB, 3904897024 bytes 4 heads, 16 sectors/track, 119168 cylinders Units = cylinders of 64 * 512 = 32768 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000
Disk /dev/mmcblk1 doesn't contain a valid partition table
root@localhost:~/flashbench# factor 3904897024 3904897024: 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 7 7 19
root@localhost:~/flashbench# ./flashbench /dev/mmcblk1 --open-au --erasesize=$[4*1024*1024] --blocksize=$[16*1024] --open-au-nr=1 4MiB 6.45M/s 2MiB 5.19M/s 1MiB 5.19M/s 512KiB 5.1M/s 256KiB 5.15M/s 128KiB 5.14M/s 64KiB 5.1M/s 32KiB 4.94M/s 16KiB 3.71M/s root@localhost:~/flashbench# ./flashbench /dev/mmcblk1 --open-au --erasesize=$[4*1024*1024] --blocksize=$[16*1024] --open-au-nr=2 4MiB 3.88M/s 2MiB 5.19M/s 1MiB 5.12M/s 512KiB 5.06M/s 256KiB 4.99M/s 128KiB 4.77M/s 64KiB 4.64M/s 32KiB 4.53M/s 16KiB 3.38M/s root@localhost:~/flashbench# ./flashbench /dev/mmcblk1 --open-au --erasesize=$[4*1024*1024] --blocksize=$[16*1024] --open-au-nr=3 4MiB 4.47M/s 2MiB 5.19M/s 1MiB 5.17M/s 512KiB 5.12M/s 256KiB 4.96M/s 128KiB 4.77M/s 64KiB 4.65M/s 32KiB 4.49M/s 16KiB 3.36M/s root@localhost:~/flashbench# ./flashbench /dev/mmcblk1 --open-au --erasesize=$[4*1024*1024] --blocksize=$[16*1024] --open-au-nr=4 4MiB 6.06M/s 2MiB 4.49M/s 1MiB 2.82M/s 512KiB 1.25M/s 256KiB 607K/s 128KiB 302K/s ^C
root@localhost:~/flashbench# ./flashbench /dev/mmcblk1 --open-au --erasesize=$[4*1024*1024] --blocksize=$[16*1024] --random --open-au-nr=1 4MiB 3.07M/s 2MiB 2.13M/s 1MiB 3.24M/s 512KiB 1.44M/s 256KiB 1.76M/s 128KiB 1.91M/s 64KiB 1.36M/s 32KiB 1.18M/s 16KiB 1.2M/s root@localhost:~/flashbench# ./flashbench /dev/mmcblk1 --open-au --erasesize=$[4*1024*1024] --blocksize=$[16*1024] --random --open-au-nr=2 4MiB 3.03M/s 2MiB 2.58M/s 1MiB 3.26M/s 512KiB 1.44M/s 256KiB 1.75M/s 128KiB 1.9M/s 64KiB 1.36M/s 32KiB 1.17M/s 16KiB 1.18M/s root@localhost:~/flashbench# ./flashbench /dev/mmcblk1 --open-au --erasesize=$[4*1024*1024] --blocksize=$[16*1024] --random --open-au-nr=3 4MiB 3.03M/s 2MiB 2.78M/s 1MiB 3.25M/s 512KiB 1.44M/s 256KiB 1.76M/s 128KiB 1.9M/s 64KiB 1.36M/s 32KiB 1.18M/s 16KiB 1.19M/s root@localhost:~/flashbench# ./flashbench /dev/mmcblk1 --open-au --erasesize=$[4*1024*1024] --blocksize=$[16*1024] --random --open-au-nr=4 4MiB 3.33M/s 2MiB 2.92M/s 1MiB 2.48M/s 512KiB 1.2M/s 256KiB 595K/s 128KiB 298K/s 64KiB 150K/s ^C
root@localhost:~/flashbench# ./flashbench /dev/mmcblk1 --find-fat --erasesize=$[4*1024*1024] 4MiB 865K/s 3.56M/s 3.01M/s 5.13M/s 5.14M/s 5.12M/s 2MiB 4.3M/s 4.88M/s 5.11M/s 5.16M/s 5.11M/s 5.3M/s 1MiB 3.99M/s 4.9M/s 5.23M/s 5.18M/s 5.17M/s 5.15M/s 512KiB 3.88M/s 4.81M/s 5.15M/s 5.16M/s 5.16M/s 5.15M/s 256KiB 4.35M/s 4.38M/s 5.17M/s 5.18M/s 5.17M/s 5.16M/s 128KiB 3.78M/s 4.8M/s 5.13M/s 5.12M/s 5.15M/s 5.14M/s 64KiB 4.27M/s 4.74M/s 5.08M/s 5.03M/s 5.08M/s 5.07M/s 32KiB 3.62M/s 4.29M/s 4.97M/s 4.96M/s 4.96M/s 4.95M/s 16KiB 3.01M/s 3.31M/s 3.74M/s 4.29M/s 4.3M/s 4.29M/s