I wanted to find out if the Sandisk Netbook Edition does anything particularly well for Netbooks. Apparently this is not the case, it's a standard Sandisk Algorithm for older cards. Well, 20€ wasted ;-)

This card can write random access to 6 2MB allocation units, but does not store a lookup table, so it always needs to garbage-collect the allocation unit when it does this, making random access relatively slow.

Minimum size for random-access writes is 64 KB, anything smaller seems to do 64 KB copy-on-write.

As a twist, it can do random access to 4 segments, but linear access to 6 segments.

$ head /sys/block/mmcblk0/device/{cid,csd,scr,*rev,*id,name,serial} ==> /sys/block/mmcblk0/device/cid <== 035344534430384780708b1879009500 ==> /sys/block/mmcblk0/device/csd <== 400e00325b5900003b377f800a404000 ==> /sys/block/mmcblk0/device/scr <== 0235000000000000 ==> /sys/block/mmcblk0/device/fwrev <== 0x0 ==> /sys/block/mmcblk0/device/hwrev <== 0x8 ==> /sys/block/mmcblk0/device/cid <== 035344534430384780708b1879009500 ==> /sys/block/mmcblk0/device/manfid <== 0x000003 ==> /sys/block/mmcblk0/device/oemid <== 0x5344 ==> /sys/block/mmcblk0/device/name <== SD08G ==> /sys/block/mmcblk0/device/serial <== 0x708b1879

$ sudo ./flashbench --open-au --open-au-nr=1 /dev/mmcblk0 --blocksize=8192 \ --erasesize=$[2* 1024 * 1024] --random 2MiB 5.34M/s 1MiB 3.01M/s 512KiB 2.39M/s 256KiB 2.34M/s 128KiB 2.37M/s 64KiB 2.31M/s 32KiB 1.69M/s 16KiB 1.69M/s 8KiB 861K/s

$ sudo ./flashbench --open-au --open-au-nr=4 /dev/mmcblk0 --blocksize=8192 --erasesize=$[2* 1024 * 1024] --random 2MiB 4.08M/s 1MiB 4.96M/s 512KiB 3.05M/s 256KiB 2.36M/s 128KiB 2.33M/s 64KiB 2.3M/s 32KiB 1.91M/s 16KiB 1.61M/s 8KiB 835K/s

$ sudo ./flashbench --open-au --open-au-nr=5 /dev/mmcblk0 --blocksize=8192 \ --erasesize=$[2* 1024 * 1024] --random 2MiB 3.32M/s 1MiB 4.5M/s 512KiB 3.11M/s 256KiB 2.27M/s 128KiB 2.14M/s 64KiB 1.38M/s 32KiB 715K/s 16KiB 395K/s 8KiB 193K/s

$ sudo ./flashbench --open-au --open-au-nr=6 /dev/mmcblk0 --blocksize=1024 \ --erasesize=$[2* 1024 * 1024] 2MiB 5.36M/s 1MiB 5.38M/s 512KiB 5.38M/s 256KiB 5.38M/s 128KiB 5.38M/s 64KiB 5.38M/s 32KiB 4.54M/s 16KiB 3.46M/s 8KiB 2.59M/s 4KiB 1.35M/s 2KiB 631K/s 1KiB 308K/s

$ sudo ./flashbench --open-au --open-au-nr=7 /dev/mmcblk0 --blocksize=1024 --erasesize=$[2* 1024 * 1024] 2MiB 5.42M/s 1MiB 4.19M/s 512KiB 2.15M/s 256KiB 1.12M/s 128KiB 583K/s 64KiB 299K/s 32KiB 152K/s ^C

$ sudo ./flashbench --findfat --fat-nr=10 /dev/mmcblk0 --blocksize=1024 --erasesize=$[2* 1024 * 1024] --random 2MiB 5.29M/s 5.37M/s 5.38M/s 3.34M/s 3.33M/s 3.35M/s 3.35M/s 3.37M/s 5.33M/s 5.37M/s 1MiB 4.3M/s 4.36M/s 4.37M/s 3.26M/s 4.36M/s 2.24M/s 3.65M/s 3.49M/s 3.67M/s 3.69M/s 512KiB 3.32M/s 3.36M/s 3.36M/s 3.19M/s 3.34M/s 3.36M/s 3.35M/s 3.35M/s 3.36M/s 3.34M/s 256KiB 3.94M/s 3.95M/s 3.91M/s 3.86M/s 3.93M/s 3.94M/s 3.8M/s 3.93M/s 3.94M/s 3.92M/s 128KiB 4.35M/s 4.35M/s 4.34M/s 4.19M/s 4.34M/s 4.35M/s 4.35M/s 4.23M/s 4.35M/s 4.35M/s 64KiB 4.47M/s 4.58M/s 4.58M/s 4.46M/s 4.56M/s 4.57M/s 4.57M/s 4.48M/s 4.56M/s 4.55M/s 32KiB 3.67M/s 3.77M/s 3.73M/s 3.7M/s 3.76M/s 3.72M/s 3.76M/s 3.72M/s 3.74M/s 3.72M/s 16KiB 2.63M/s 2.64M/s 2.65M/s 2.62M/s 2.56M/s 2.61M/s 2.62M/s 2.62M/s 2.6M/s 2.61M/s 8KiB 1.45M/s 1.47M/s 1.48M/s 1.46M/s 1.45M/s 1.46M/s 1.46M/s 1.44M/s 1.47M/s 1.47M/s 4KiB 647K/s 645K/s 643K/s 644K/s 642K/s 642K/s 638K/s 637K/s 638K/s 637K/s