arnd@wuerfel:~/flashbench$ sudo ./flashbench -a /dev/sdd --blocksize=1024 align 536870912 pre 1.12ms on 1.51ms post 1.46ms diff 219µs align 268435456 pre 1.1ms on 1.52ms post 1.44ms diff 241µs align 134217728 pre 1.19ms on 1.54ms post 1.44ms diff 226µs align 67108864 pre 1.19ms on 1.53ms post 1.44ms diff 216µs align 33554432 pre 1.17ms on 1.52ms post 1.44ms diff 208µs align 16777216 pre 1.17ms on 1.55ms post 1.44ms diff 245µs align 8388608 pre 1.21ms on 1.57ms post 1.48ms diff 228µs align 4194304 pre 1.21ms on 1.53ms post 1.42ms diff 209µs align 2097152 pre 1.22ms on 1.58ms post 1.44ms diff 252µs align 1048576 pre 1.19ms on 1.56ms post 1.44ms diff 248µs align 524288 pre 1.23ms on 1.54ms post 1.44ms diff 208µs align 262144 pre 1.19ms on 1.52ms post 1.46ms diff 189µs align 131072 pre 1.21ms on 1.55ms post 1.45ms diff 221µs align 65536 pre 1.19ms on 1.48ms post 1.44ms diff 164µs align 32768 pre 1.19ms on 1.51ms post 1.44ms diff 192µs align 16384 pre 1.19ms on 1.52ms post 1.46ms diff 199µs align 8192 pre 1.21ms on 1.54ms post 1.46ms diff 205µs align 4096 pre 1.35ms on 1.32ms post 1.3ms diff -6829ns align 2048 pre 1.42ms on 1.42ms post 1.37ms diff 27.7µs arnd@wuerfel:~/flashbench$ sudo ./flashbench -a /dev/sdd --blocksize=3072 align 402653184 pre 1.24ms on 1.71ms post 1.52ms diff 336µs align 201326592 pre 1.32ms on 1.69ms post 1.51ms diff 279µs align 100663296 pre 1.32ms on 1.69ms post 1.52ms diff 278µs align 50331648 pre 1.31ms on 1.69ms post 1.51ms diff 280µs align 25165824 pre 1.32ms on 1.69ms post 1.52ms diff 277µs align 12582912 pre 1.31ms on 1.69ms post 1.51ms diff 283µs align 6291456 pre 1.32ms on 1.73ms post 1.51ms diff 315µs align 3145728 pre 1.34ms on 1.73ms post 1.53ms diff 294µs align 1572864 pre 1.35ms on 1.6ms post 1.51ms diff 172µs align 786432 pre 1.35ms on 1.6ms post 1.51ms diff 169µs align 393216 pre 1.35ms on 1.6ms post 1.51ms diff 171µs align 196608 pre 1.35ms on 1.59ms post 1.51ms diff 155µs align 98304 pre 1.35ms on 1.55ms post 1.52ms diff 120µs align 49152 pre 1.34ms on 1.58ms post 1.52ms diff 159µs align 24576 pre 1.33ms on 1.59ms post 1.53ms diff 155µs align 12288 pre 1.46ms on 1.46ms post 1.34ms diff 62.3µs align 6144 pre 1.39ms on 1.35ms post 1.55ms diff -115362
arnd@wuerfel:~/flashbench$ cat /proc/partitions major minor #blocks name 8 48 3879936 sdd 8 49 3875840 sdd1 arnd@wuerfel:~/flashbench$ factor 3879936 3879936: 2 2 2 2 2 2 2 2 2 2 3 3 421 arnd@wuerfel:~/flashbench$ echo $[3879936 / 421 / 3] 3072
arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] -- blocksize=3072 --open-au-nr=1 /dev/sdd 3MiB 7.07M/s 1.5MiB 7.06M/s 768KiB 7.04M/s 384KiB 6.82M/s 192KiB 6.92M/s 96KiB 7.07M/s 48KiB 6.39M/s 24KiB 5.13M/s 12KiB 3.61M/s 6KiB 2.49M/s 3KiB 1.61M/s
arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] -- blocksize=3072 --open-au-nr=1 /dev/sdd --random 3MiB 7.13M/s 1.5MiB 6.81M/s 768KiB 6.7M/s 384KiB 6.52M/s 192KiB 6.17M/s 96KiB 6.59M/s 48KiB 5.64M/s 24KiB 3.75M/s 12KiB 2.16M/s 6KiB 981K/s 3KiB 522K/s
arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] -- blocksize=3072 --open-au-nr=1 /dev/sdd 3MiB 7.07M/s 1.5MiB 7.06M/s 768KiB 7.04M/s 384KiB 6.82M/s 192KiB 6.92M/s 96KiB 7.07M/s 48KiB 6.39M/s 24KiB 5.13M/s 12KiB 3.61M/s 6KiB 2.49M/s 3KiB 1.61M/s arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] -- blocksize=3072 --open-au-nr=1 /dev/sdd --random 3MiB 7.13M/s 1.5MiB 6.81M/s 768KiB 6.7M/s 384KiB 6.52M/s 192KiB 6.17M/s 96KiB 6.59M/s 48KiB 5.64M/s 24KiB 3.75M/s 12KiB 2.16M/s 6KiB 981K/s 3KiB 522K/s arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] -- blocksize=$[4*3072] --open-au-nr=4 /dev/sdd --random 3MiB 6.96M/s 1.5MiB 4.16M/s 768KiB 6.59M/s 384KiB 6.4M/s 192KiB 6.34M/s 96KiB 6.62M/s 48KiB 5.72M/s 24KiB 3.72M/s 12KiB 2.14M/s arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] -- blocksize=$[4*3072] --open-au-nr=8 /dev/sdd --random 3MiB 4.98M/s 1.5MiB 1.92M/s 768KiB 1.05M/s ^Carnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] - locksize=$[4*3072] --open-au-nr=5 /dev/sdd --random 3MiB 5.38M/s 1.5MiB 4.28M/s 768KiB 6.45M/s 384KiB 6.39M/s 192KiB 6.26M/s 96KiB 6.52M/s 48KiB 5.62M/s 24KiB 3.72M/s 12KiB 2.15M/s arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] -- blocksize=$[4*3072] --open-au-nr=6 /dev/sdd --random 3MiB 5.4M/s 1.5MiB 1.96M/s 768KiB 1.05M/s 384KiB 567K/s 192KiB 406K/s 96KiB 465K/s 48KiB 344K/s 24KiB 322K/s 12KiB 168K/s
arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] -- blocksize=$[4*3072] --open-au-nr=5 /dev/sdd 3MiB 4.9M/s 1.5MiB 6.76M/s 768KiB 6.61M/s 384KiB 6.34M/s 192KiB 6.47M/s 96KiB 6.6M/s 48KiB 5.93M/s 24KiB 4M/s 12KiB 2.78M/s arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[3072 * 1024] -- blocksize=$[4*3072] --open-au-nr=6 /dev/sdd 3MiB 5.46M/s 1.5MiB 1.81M/s 768KiB 1.05M/s
arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[1024 * 1024] - locksize=$[1024] --open-au-nr=5 /dev/sdd 1MiB 6.75M/s 512KiB 6.54M/s 256KiB 6.44M/s 128KiB 6.03M/s 64KiB 6.21M/s 32KiB 5.27M/s 16KiB 4.02M/s 8KiB 2.39M/s 4KiB 1.24M/s 2KiB 667K/s 1KiB 389K/s arnd@wuerfel:~/flashbench$ sudo ./flashbench --open-au --erasesize=$[1024 * 1024] -- blocksize=$[16*1024] --open-au-nr=6 /dev/sdd 1MiB 1.5M/s 512KiB 723K/s 256KiB 426K/s
arnd@wuerfel:~/flashbench$ sudo dd if=/dev/zero of=/dev/sdd bs=3M seek=20 count=50 oflag=direct 50+0 records in 50+0 records out 157286400 bytes (157 MB) copied, 22.6699 s, 6.9 MB/s arnd@wuerfel:~/flashbench$ sudo dd of=/dev/zero if=/dev/sdd bs=3M seek=20 count=50 iflag=direct 50+0 records in 50+0 records out 157286400 bytes (157 MB) copied, 10.7294 s, 14.7 MB/s