Just received a new SanDisk Mobile Ultra 8GB microSD card. Tests done on my HP Elitebook 8560w with Debian 6 and 2.6.38 kernel. Card is direct out of the packaging and into tests.
It looks like 4MB erase blocks and either 8kB or 32kB pages, but I'm not really sure. Tests done with 8kB blocksize. 6 connections work well, 7 and 8 fall off quickly in performance.
If there's any other info needed, please let me know. -Andrew
andrew@bradford:~/flashbench$ sudo head /sys/block/mmcblk0/device/* 2>/dev/null | grep -v ^$ ==> /sys/block/mmcblk0/device/block <== ==> /sys/block/mmcblk0/device/cid <== 035344535530384780716a01f200bb00 ==> /sys/block/mmcblk0/device/csd <== 400e00325b5900003b377f800a404000 ==> /sys/block/mmcblk0/device/date <== 11/2011 ==> /sys/block/mmcblk0/device/driver <== ==> /sys/block/mmcblk0/device/erase_size <== 512 ==> /sys/block/mmcblk0/device/fwrev <== 0x0 ==> /sys/block/mmcblk0/device/hwrev <== 0x8 ==> /sys/block/mmcblk0/device/manfid <== 0x000003 ==> /sys/block/mmcblk0/device/name <== SU08G ==> /sys/block/mmcblk0/device/oemid <== 0x5344 ==> /sys/block/mmcblk0/device/power <== ==> /sys/block/mmcblk0/device/preferred_erase_size <== 4194304 ==> /sys/block/mmcblk0/device/scr <== 0235800300000000 ==> /sys/block/mmcblk0/device/serial <== 0x716a01f2 ==> /sys/block/mmcblk0/device/subsystem <== ==> /sys/block/mmcblk0/device/type <== SD ==> /sys/block/mmcblk0/device/uevent <== DRIVER=mmcblk MMC_TYPE=SD MMC_NAME=SU08G MODALIAS=mmc:block
andrew@bradford:~/flashbench$ sudo fdisk -l /dev/mmcblk0
Disk /dev/mmcblk0: 7948 MB, 7948206080 bytes 81 heads, 10 sectors/track, 19165 cylinders Units = cylinders of 810 * 512 = 414720 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000
Device Boot Start End Blocks Id System /dev/mmcblk0p1 11 19166 7757824 b W95 FAT32
andrew@bradford:~/flashbench$ sudo ./flashbench -a /dev/mmcblk0 --blocksize=1024 align 2147483648 pre 508µs on 575µs post 467µs diff 87.3µs align 1073741824 pre 518µs on 601µs post 469µs diff 107µs align 536870912 pre 526µs on 600µs post 469µs diff 103µs align 268435456 pre 509µs on 598µs post 468µs diff 110µs align 134217728 pre 526µs on 599µs post 469µs diff 102µs align 67108864 pre 519µs on 597µs post 467µs diff 104µs align 33554432 pre 515µs on 598µs post 468µs diff 106µs align 16777216 pre 510µs on 594µs post 466µs diff 106µs align 8388608 pre 508µs on 584µs post 465µs diff 97.4µs align 4194304 pre 492µs on 593µs post 480µs diff 107µs align 2097152 pre 480µs on 478µs post 468µs diff 4.16µs align 1048576 pre 482µs on 481µs post 470µs diff 5.2µs align 524288 pre 482µs on 482µs post 467µs diff 7.22µs align 262144 pre 480µs on 479µs post 469µs diff 4.83µs align 131072 pre 480µs on 480µs post 467µs diff 7.06µs align 65536 pre 480µs on 480µs post 470µs diff 4.72µs align 32768 pre 479µs on 480µs post 464µs diff 8.17µs align 16384 pre 481µs on 478µs post 470µs diff 3.09µs align 8192 pre 468µs on 471µs post 470µs diff 1.54µs align 4096 pre 481µs on 464µs post 467µs diff -9689ns align 2048 pre 451µs on 456µs post 456µs diff 2.33µs
andrew@bradford:~/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[4 * 1024 * 1024] --blocksize=$[8 * 1024] --open-au-nr=1 4MiB 10.7M/s 2MiB 10.7M/s 1MiB 10.7M/s 512KiB 10.7M/s 256KiB 10.6M/s 128KiB 10.6M/s 64KiB 10.6M/s 32KiB 9.53M/s 16KiB 8.09M/s 8KiB 5.99M/s
andrew@bradford:~/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[4 * 1024 * 1024] --blocksize=$[8 * 1024] --open-au-nr=6 4MiB 10.6M/s 2MiB 10.7M/s 1MiB 10.6M/s 512KiB 10.6M/s 256KiB 10.6M/s 128KiB 10.4M/s 64KiB 10.3M/s 32KiB 9.04M/s 16KiB 7.36M/s 8KiB 5.19M/s
andrew@bradford:~/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[4 * 1024 * 1024] --blocksize=$[8 * 1024] --open-au-nr=7 4MiB 6.55M/s 2MiB 7.04M/s 1MiB 5.81M/s 512KiB 5.77M/s 256KiB 5.65M/s 128KiB 5.57M/s 64KiB 6.52M/s 32KiB 7.24M/s 16KiB 6.29M/s 8KiB 4.69M/s
andrew@bradford:~/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[4 * 1024 * 1024] --blocksize=$[8 * 1024] --open-au-nr=8 4MiB 7.08M/s 2MiB 5.53M/s 1MiB 3.9M/s 512KiB 4.7M/s 256KiB 4.05M/s 128KiB 4.54M/s 64KiB 5.84M/s 32KiB 6.28M/s 16KiB 5.66M/s 8KiB 614K/s
ndrew@bradford:~/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[4 * 1024 * 1024] --blocksize=$[8 * 1024] --open-au-nr=2 --random 4MiB 10.4M/s 2MiB 10.6M/s 1MiB 10.6M/s 512KiB 10.5M/s 256KiB 8.4M/s 128KiB 4.36M/s 64KiB 2.39M/s 32KiB 1.23M/s 16KiB 604K/s 8KiB 2.23M/s
andrew@bradford:~/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[4 * 1024 * 1024] --blocksize=$[8 * 1024] --open-au-nr=6 --random 4MiB 8.06M/s 2MiB 6.91M/s 1MiB 10.6M/s 512KiB 10.6M/s 256KiB 8.44M/s 128KiB 4.37M/s 64KiB 2.4M/s 32KiB 1.23M/s 16KiB 606K/s 8KiB 1.9M/s
andrew@bradford:~/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[4 * 1024 * 1024] --blocksize=$[8 * 1024] --open-au-nr=7 --random 4MiB 6.65M/s 2MiB 6.52M/s 1MiB 5.75M/s 512KiB 4.01M/s 256KiB 2.93M/s 128KiB 1.73M/s 64KiB 952K/s 32KiB 533K/s 16KiB 365K/s 8KiB 1.35M/s