andrew@brick:~/git/flashbench$ head /sys/block/mmcblk0/device/* 2>/dev/null | grep -v ^$ ==> /sys/block/mmcblk0/device/block <== ==> /sys/block/mmcblk0/device/cid <== 1b534d30303030301091ce109c00d500 ==> /sys/block/mmcblk0/device/csd <== 400e00325b5900001d4d7f800a400000 ==> /sys/block/mmcblk0/device/date <== 05/2013 ==> /sys/block/mmcblk0/device/driver <== ==> /sys/block/mmcblk0/device/erase_size <== 512 ==> /sys/block/mmcblk0/device/fwrev <== 0x0 ==> /sys/block/mmcblk0/device/hwrev <== 0x1 ==> /sys/block/mmcblk0/device/manfid <== 0x00001b ==> /sys/block/mmcblk0/device/name <== 00000 ==> /sys/block/mmcblk0/device/oemid <== 0x534d ==> /sys/block/mmcblk0/device/power <== ==> /sys/block/mmcblk0/device/preferred_erase_size <== 4194304 ==> /sys/block/mmcblk0/device/scr <== 0235000000000000 ==> /sys/block/mmcblk0/device/serial <== 0x91ce109c ==> /sys/block/mmcblk0/device/subsystem <== ==> /sys/block/mmcblk0/device/type <== SD ==> /sys/block/mmcblk0/device/uevent <== DRIVER=mmcblk MMC_TYPE=SD MMC_NAME=00000 MODALIAS=mmc:block

andrew@brick:~/git/flashbench$ sudo fdisk -l /dev/mmcblk0

Disk /dev/mmcblk0: 3933 MB, 3933208576 bytes, 7682048 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x00000000

Device Boot Start End Blocks Id System /dev/mmcblk0p1 8192 7682047 3836928 b W95 FAT32

andrew@brick:~/git/flashbench$ factor 3933208576 3933208576: 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 11 11 31

andrew@brick:~/git/flashbench$ sudo ./flashbench -a /dev/mmcblk0 --blocksize=1024 --count=100 align 1073741824 pre 336µs on 423µs post 408µs diff 50.8µs align 536870912 pre 341µs on 424µs post 417µs diff 45.4µs align 268435456 pre 330µs on 410µs post 405µs diff 42.8µs align 134217728 pre 324µs on 399µs post 407µs diff 33.5µs align 67108864 pre 325µs on 399µs post 408µs diff 32.6µs align 33554432 pre 325µs on 399µs post 407µs diff 32.8µs align 16777216 pre 325µs on 399µs post 408µs diff 32.4µs align 8388608 pre 331µs on 416µs post 415µs diff 42.7µs align 4194304 pre 340µs on 424µs post 425µs diff 41.6µs align 2097152 pre 341µs on 430µs post 422µs diff 48.9µs align 1048576 pre 337µs on 430µs post 427µs diff 48µs align 524288 pre 340µs on 402µs post 423µs diff 21µs align 262144 pre 335µs on 402µs post 426µs diff 21.2µs align 131072 pre 339µs on 402µs post 421µs diff 21.4µs align 65536 pre 336µs on 402µs post 426µs diff 20.8µs align 32768 pre 339µs on 401µs post 423µs diff 20.2µs align 16384 pre 336µs on 401µs post 424µs diff 20.6µs align 8192 pre 336µs on 394µs post 418µs diff 17.5µs align 4096 pre 381µs on 377µs post 370µs diff 877ns align 2048 pre 405µs on 400µs post 394µs diff 1.01µs

## 1 MiB erase blocks

andrew@brick:~/git/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[1024*1024] --blocksize=$[8*1024] --open-au-nr=1 1MiB 3.07M/s 512KiB 4.7M/s 256KiB 8.76M/s 128KiB 8.59M/s 64KiB 5.31M/s 32KiB 3.01M/s 16KiB 6.89M/s 8KiB 4.46M/s andrew@brick:~/git/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[1024*1024] --blocksize=$[8*1024] --open-au-nr=2 1MiB 8.93M/s 512KiB 8.88M/s 256KiB 8.91M/s 128KiB 8.91M/s 64KiB 8.8M/s 32KiB 8.53M/s 16KiB 6.77M/s 8KiB 4.43M/s andrew@brick:~/git/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[1024*1024] --blocksize=$[8*1024] --open-au-nr=3 1MiB 3.02M/s 512KiB 1.87M/s 256KiB 1.19M/s 128KiB 630K/s 64KiB 406K/s 32KiB 408K/s 16KiB 398K/s 8KiB 2.09M/s andrew@brick:~/git/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[1024*1024] --blocksize=$[8*1024] --random --open-au-nr=1 1MiB 9.01M/s 512KiB 8.97M/s 256KiB 1.72M/s 128KiB 8.94M/s 64KiB 8.91M/s 32KiB 8.72M/s 16KiB 7.04M/s 8KiB 4.59M/s andrew@brick:~/git/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[1024*1024] --blocksize=$[8*1024] --random --open-au-nr=2 1MiB 8.2M/s 512KiB 8.95M/s 256KiB 8.89M/s 128KiB 8.86M/s 64KiB 8.67M/s 32KiB 8.35M/s 16KiB 6.64M/s 8KiB 4.22M/s andrew@brick:~/git/flashbench$ sudo ./flashbench /dev/mmcblk0 --open-au --erasesize=$[1024*1024] --blocksize=$[8*1024] --random --open-au-nr=3 1MiB 1.81M/s 512KiB 1.45M/s 256KiB 1.02M/s 128KiB 689K/s 64KiB 439K/s 32KiB 390K/s 16KiB 397K/s 8KiB 2.46M/s

## 2 open-au linear and random

andrew@brick:~/git/flashbench$ sudo ./flashbench --find-fat --erasesize=$[1024*1024] --fat-nr=16 /dev/mmcblk0 1MiB 1.75M/s 8.97M/s 8.8M/s 1.7M/s 5.05M/s 5.5M/s 6.44M/s 6.57M/s 6.43M/s 6.4M/s 6.67M/s 6.36M/s 6.5M/s 6.67M/s 6.33M/s 6.45M/s 512KiB 6.47M/s 6.36M/s 8.92M/s 4.34M/s 2.97M/s 4.66M/s 5.03M/s 6.03M/s 6.57M/s 6.65M/s 6.26M/s 6.65M/s 6.57M/s 6.32M/s 6.68M/s 6.49M/s 256KiB 6.21M/s 6.62M/s 6.61M/s 4.3M/s 2.97M/s 4.57M/s 4.98M/s 5.99M/s 6.65M/s 6.65M/s 6.28M/s 6.53M/s 6.66M/s 6.19M/s 6.53M/s 6.63M/s 128KiB 6.07M/s 6.52M/s 6.62M/s 4.35M/s 2.95M/s 4.4M/s 5.01M/s 5.9M/s 6.6M/s 6.51M/s 6.14M/s 6.6M/s 6.67M/s 6.24M/s 6.67M/s 6.68M/s 64KiB 6.14M/s 6.6M/s 6.61M/s 4.42M/s 2.96M/s 4.35M/s 4.98M/s 5.88M/s 6.49M/s 6.58M/s 6.13M/s 6.53M/s 6.47M/s 6.18M/s 6.56M/s 6.48M/s 32KiB 4.8M/s 4.98M/s 4.99M/s 7.08M/s 8.27M/s 7.97M/s 7.63M/s 8.17M/s 8.23M/s 8.34M/s 8.41M/s 8.11M/s 4.08M/s 2.91M/s 4.57M/s 4.86M/s 16KiB 2.65M/s 3.71M/s 6.54M/s 6.54M/s 6.51M/s 6.6M/s 6.68M/s 6.52M/s 6.53M/s 6.79M/s 6.83M/s 7M/s 5.19M/s 3.45M/s 3.38M/s 5.21M/s