arnd@wuerfel:~/flashbench$ sudo fdisk -lu /dev/sdc
Disk /dev/sdc: 4009 MB, 4009549824 bytes 255 heads, 63 sectors/track, 487 cylinders, total 7831152 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 identifier: 0x001c2022
Device Boot Start End Blocks Id System /dev/sdc1 * 63 7830143 3915040+ b W95 FAT32 Partition 1 has different physical/logical endings: phys=(1023, 254, 63) logical=(487, 102, 63)
arnd@wuerfel:~/flashbench$ sudo ./flashbench -a /dev/sdc --blocksize 1024 align 536870912 pre 615µs on 744µs post 497µs diff 188µs align 268435456 pre 607µs on 743µs post 530µs diff 174µs align 134217728 pre 618µs on 744µs post 535µs diff 167µs align 67108864 pre 618µs on 745µs post 574µs diff 149µs align 33554432 pre 618µs on 743µs post 500µs diff 185µs align 16777216 pre 621µs on 748µs post 518µs diff 178µs align 8388608 pre 618µs on 745µs post 517µs diff 177µs align 4194304 pre 628µs on 758µs post 551µs diff 168µs align 2097152 pre 549µs on 659µs post 568µs diff 100µs align 1048576 pre 553µs on 655µs post 550µs diff 104µs align 524288 pre 534µs on 658µs post 535µs diff 124µs align 262144 pre 536µs on 656µs post 535µs diff 120µs align 131072 pre 591µs on 655µs post 618µs diff 50.2µs align 65536 pre 567µs on 656µs post 569µs diff 88.2µs align 32768 pre 553µs on 657µs post 534µs diff 113µs align 16384 pre 553µs on 653µs post 569µs diff 92.4µs align 8192 pre 551µs on 656µs post 550µs diff 105µs align 4096 pre 534µs on 658µs post 535µs diff 124µs align 2048 pre 545µs on 656µs post 569µs diff 98.7µs
arnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=4194304 --blocksi=512 --open-au --open-au-nr=1 4MiB 10.7M/s 2MiB 10.6M/s 1MiB 10.7M/s 512KiB 10.4M/s 256KiB 10.8M/s 128KiB 9.66M/s 64KiB 11.8M/s 32KiB 10.1M/s 16KiB 8.22M/s 8KiB 3.74M/s 4KiB 1.83M/s 2KiB 900K/s 1KiB 451K/s 512B 224K/s arnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=$[4194304] --blocksize=16384 --open-au --open-au-nr=2 4MiB 10.8M/s 2MiB 10.6M/s 1MiB 10.7M/s 512KiB 10.5M/s 256KiB 10.5M/s 128KiB 9.07M/s 64KiB 10.1M/s 32KiB 7.75M/s 16KiB 5.43M/s arnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=$[4194304] --blocksize=16384 --open-au --open-au-nr=4 4MiB 10.8M/s 2MiB 10.6M/s 1MiB 10.7M/s 512KiB 10.5M/s 256KiB 10.5M/s 128KiB 8.98M/s 64KiB 10M/s 32KiB 7.71M/s 16KiB 5.42M/s arnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=$[4194304] --blocksize=16384 --open-au --open-au-nr=6 4MiB 10.8M/s 2MiB 10.6M/s 1MiB 10.6M/s 512KiB 10.6M/s 256KiB 10.4M/s 128KiB 8.96M/s 64KiB 10M/s 32KiB 7.68M/s 16KiB 5.39M/s arnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=$[4194304] --blocksize=1024 --open-au --open-au-nr=11 4MiB 10.8M/s 2MiB 10.6M/s 1MiB 10.7M/s 512KiB 10.5M/s 256KiB 10.4M/s 128KiB 8.91M/s 64KiB 9.99M/s 32KiB 7.62M/s 16KiB 5.33M/s 8KiB 2.45M/s 4KiB 1.17M/s 2KiB 579K/s 1KiB 285K/s arnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=$[4194304] --blocksize=16384 --open-au --open-au-nr=12 4MiB 10.7M/s 2MiB 4.52M/s 1MiB 1.13M/s 512KiB 561K/s 256KiB 283K/s 128KiB 142K/s
arnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=4194304 --blocksize=512 --open-au --open-au-nr=1 --random 4MiB 11M/s 2MiB 3.01M/s 1MiB 9.02M/s 512KiB 3.04M/s 256KiB 3.04M/s 128KiB 1.77M/s 64KiB 9.46M/s 32KiB 3.04M/s 16KiB 2.86M/s 8KiB 1.3M/s 4KiB 870K/s 2KiB 426K/s 1KiB 211K/s 512B 105K/s
arnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=$[4194304] --blocksize=1024 --open-au --open-au-nr=11 --random 4MiB 10.7M/s 2MiB 3.03M/s 1MiB 3.22M/s 512KiB 3.03M/s 256KiB 3M/s 128KiB 2.68M/s 64KiB 3.12M/s 32KiB 2.77M/s 16KiB 2.4M/s 8KiB 1.43M/s 4KiB 706K/s
(reverse-i-search)`da': sudo fdisk -l /dev/s^Carnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=$[4194304] --blocksize=1024 --open-au --open-au-nr=12 --random 4MiB 8.91M/s 2MiB 3.08M/s 1MiB 1.19M/s 512KiB 569K/s
^Carnd@wuerfel:~/flashbench$ sudo ./flashbench /dev/sdc --erasesize=$[4194304 * 2] --ocksize=1024 --open-au --open-au-nr=6 --random 8MiB 10M/s 4MiB 9.01M/s 2MiB 3.71M/s 1MiB 1.46M/s 512KiB 897K/s
arnd@wuerfel:~/flashbench$ sudo dd if=/dev/zero of=/dev/sdc bs=1M count=100 oflag=direct 100+0 records in 100+0 records out 104857600 bytes (105 MB) copied, 10.8724 s, 9.6 MB/s