andrew@boomboom:~/git/flashbench$ /sbin/fdisk -l /dev/sdc
Disk /dev/sdc: 32.0 GB, 32015679488 bytes 255 heads, 63 sectors/track, 3892 cylinders, total 62530624 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: 0x00000000
Device Boot Start End Blocks Id System /dev/sdc1 32 62530623 31265296 c W95 FAT32 (LBA)
andrew@boomboom:~/git/flashbench$ factor 32015679488 32015679488: 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 13 17 4421
andrew@boomboom:~/git/flashbench$ sudo ./flashbench -a /dev/sdc --count=100 --blocksize=2048 [sudo] password for andrew: align 8589934592 pre 1.05ms on 1.29ms post 1ms diff 264µs align 4294967296 pre 1.02ms on 1.41ms post 1.01ms diff 398µs align 2147483648 pre 1.07ms on 1.43ms post 1.04ms diff 372µs align 1073741824 pre 1.03ms on 1.41ms post 1.01ms diff 384µs align 536870912 pre 1.06ms on 1.4ms post 994µs diff 371µs align 268435456 pre 1.02ms on 1.4ms post 1.01ms diff 386µs align 134217728 pre 1.06ms on 1.39ms post 1.01ms diff 358µs align 67108864 pre 1.03ms on 1.39ms post 998µs diff 378µs align 33554432 pre 1.03ms on 1.4ms post 993µs diff 390µs align 16777216 pre 1.02ms on 1.38ms post 1.01ms diff 370µs align 8388608 pre 1.05ms on 1.38ms post 1.01ms diff 349µs align 4194304 pre 1.02ms on 1.24ms post 979µs diff 241µs align 2097152 pre 1.04ms on 1.06ms post 1.03ms diff 26.2µs align 1048576 pre 1.03ms on 1.03ms post 1.02ms diff -766ns align 524288 pre 974µs on 1ms post 993µs diff 19.9µs align 262144 pre 1.01ms on 1.01ms post 999µs diff 11µs align 131072 pre 994µs on 1.01ms post 992µs diff 13.5µs align 65536 pre 996µs on 1.01ms post 997µs diff 8.89µs align 32768 pre 991µs on 1ms post 1ms diff 4.32µs align 16384 pre 1ms on 1.06ms post 1.06ms diff 28.1µs align 8192 pre 996µs on 1ms post 997µs diff 3.83µs align 4096 pre 997µs on 987µs post 980µs diff -801ns
4 MiB erase blocks
andrew@boomboom:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[8*1024] --erasesize=$[4*1024*1024] --open-au-nr=1 4MiB 21.8M/s 2MiB 21.6M/s 1MiB 21.6M/s 512KiB 21.4M/s 256KiB 20.5M/s 128KiB 18.8M/s 64KiB 17.2M/s 32KiB 15.9M/s 16KiB 10.7M/s 8KiB 6.41M/s andrew@boomboom:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[8*1024] --erasesize=$[4*1024*1024] --open-au-nr=2 4MiB 21.7M/s 2MiB 21.6M/s 1MiB 21.4M/s 512KiB 21.2M/s 256KiB 20.2M/s 128KiB 18.5M/s 64KiB 16.9M/s 32KiB 14.9M/s 16KiB 10.1M/s 8KiB 5.83M/s andrew@boomboom:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[8*1024] --erasesize=$[4*1024*1024] --open-au-nr=4 4MiB 21.7M/s 2MiB 21.6M/s 1MiB 21.5M/s 512KiB 21.2M/s 256KiB 20.2M/s 128KiB 18.5M/s 64KiB 17M/s 32KiB 15M/s 16KiB 9.97M/s 8KiB 5.85M/s andrew@boomboom:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[8*1024] --erasesize=$[4*1024*1024] --open-au-nr=6 4MiB 19.4M/s 2MiB 21.5M/s 1MiB 21.4M/s 512KiB 21.2M/s 256KiB 20.1M/s 128KiB 18.4M/s 64KiB 16.7M/s 32KiB 14.6M/s 16KiB 9.77M/s 8KiB 5.71M/s andrew@boomboom:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[8*1024] --erasesize=$[4*1024*1024] --open-au-nr=7 4MiB 12.7M/s 2MiB 8.04M/s 1MiB 4.52M/s
andrew@boomboom:~/git/flashbench$ sudo ./flashbench /dev/sdc --open-au --blocksize=$[8*1024] --erasesize=$[4*1024*1024] --random --open-au-nr=1 4MiB 21.8M/s 2MiB 21.6M/s 1MiB 21.5M/s 512KiB 20.4M/s 256KiB 9.96M/s 128KiB 2.71M/s 64KiB 1.12M/s 32KiB 564K/s 16KiB 285K/s 8KiB 132K/s
andrew@boomboom:~/git/flashbench$ sudo ./flashbench /dev/sdc --find-fat 4MiB 21.8M/s 21.8M/s 21.7M/s 21.8M/s 9.03M/s 5.15M/s 2MiB 5.78M/s 21.2M/s 21.7M/s 21.6M/s 21.6M/s 21.6M/s 1MiB 21.4M/s 21.5M/s 21.5M/s 21.5M/s 21.5M/s 21.4M/s 512KiB 21.2M/s 21.3M/s 21.3M/s 21.3M/s 21.4M/s 21.4M/s 256KiB 20.4M/s 20.4M/s 20.4M/s 20.5M/s 20.5M/s 20.4M/s 128KiB 18.7M/s 18.8M/s 18.8M/s 18.8M/s 18.9M/s 18.7M/s 64KiB 16.9M/s 17M/s 17M/s 16.9M/s 16.9M/s 16.9M/s 32KiB 15.6M/s 15.1M/s 15.2M/s 15.6M/s 15.5M/s 15.2M/s 16KiB 10.2M/s 10.3M/s 10.3M/s 10.2M/s 10.2M/s 10.1M/s