sudo fdisk -l /dev/sda

Disk /dev/sda: 60.0 GB, 60022480896 bytes 255 heads, 63 sectors/track, 7297 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000

sudo fdisk -l /dev/sda

Disk /dev/sda: 60.0 GB, 60022480896 bytes 255 heads, 63 sectors/track, 7297 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000

Disk /dev/sda doesn't contain a valid partition table arnd@ocdc-kvm:~/git/flashbench$ sudo hdparm -i /dev/sda

/dev/sda:

Model=OCZ-REVODRIVE, FwRev=1.20, SerialNo=OCZ-V8WN0QLPF80W8L99 Config={ Fixed } RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=4 BuffType=unknown, BuffSize=unknown, MaxMultSect=16, MultSect=1 CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=117231408 IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120} PIO modes: pio0 pio1 pio2 pio3 pio4 DMA modes: mdma0 mdma1 mdma2 UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5 udma6 AdvancedPM=no WriteCache=disabled Drive conforms to: unknown: ATA/ATAPI-2,3,4,5,6,7

* signifies the current active mode

sudo hdparm -W0 /dev/sda

/dev/sda: setting drive write-caching to 0 (off) write-caching = 0 (off)

$ sudo ./flashbench -a /dev/sda --count=100 align 8589934592 pre 108µs on 124µs post 90.8µs diff 25µs align 4294967296 pre 102µs on 108µs post 91.1µs diff 11.5µs align 2147483648 pre 108µs on 127µs post 91.4µs diff 27.2µs align 1073741824 pre 113µs on 132µs post 91.1µs diff 30.3µs align 536870912 pre 114µs on 134µs post 92.5µs diff 30.9µs align 268435456 pre 123µs on 144µs post 90.9µs diff 37.5µs align 134217728 pre 100µs on 117µs post 91.7µs diff 20.8µs align 67108864 pre 117µs on 140µs post 105µs diff 29.4µs align 33554432 pre 116µs on 136µs post 91.3µs diff 32.4µs align 16777216 pre 109µs on 129µs post 92.6µs diff 28µs align 8388608 pre 120µs on 144µs post 90.8µs diff 38.2µs align 4194304 pre 91.5µs on 91.6µs post 91.1µs diff 244ns align 2097152 pre 91.1µs on 91µs post 91µs diff -56ns align 1048576 pre 91.2µs on 91µs post 91.3µs diff -186ns align 524288 pre 91µs on 90.9µs post 91.1µs diff -132ns align 262144 pre 91.5µs on 91.2µs post 91.4µs diff -288ns align 131072 pre 91.4µs on 91.3µs post 91.3µs diff -92ns align 65536 pre 91.4µs on 91µs post 91.3µs diff -345ns align 32768 pre 90.9µs on 91.2µs post 91.3µs diff 142ns

time sudo ./flashbench --erasesize=8388608 /dev/sda --blocksize=4096 -p [sudo] password for arnd: 2MiB 209M/s 236M/s 103M/s 198M/s 234M/s 234M/s 101M/s 195M/s 1MiB 228M/s 230M/s 103M/s 194M/s 228M/s 231M/s 96.7M/s 200M/s 512KiB 216M/s 224M/s 105M/s 180M/s 220M/s 226M/s 86.2M/s 190M/s 256KiB 203M/s 210M/s 114M/s 174M/s 200M/s 207M/s 120M/s 175M/s 128KiB 178M/s 189M/s 129M/s 153M/s 182M/s 183M/s 128M/s 157M/s 64KiB 152M/s 156M/s 141M/s 145M/s 187M/s 195M/s 129M/s 133M/s 32KiB 162M/s 177M/s 142M/s 118M/s 173M/s 182M/s 135M/s 108M/s 16KiB 140M/s 143M/s 134M/s 88.1M/s 139M/s 143M/s 135M/s 86.2M/s 8KiB 96.2M/s 98M/s 96M/s 68.3M/s 97.8M/s 98.7M/s 95.7M/s 64M/s 4KiB 63.2M/s 60M/s 60.1M/s 41.6M/s 62.8M/s 61.1M/s 60.1M/s 41.6M/s 2KiB 20.3M/s 25M/s 24.8M/s 25.4M/s 14.3M/s 19.1M/s 14.8M/s 20.3M/s 1KiB 12.6M/s 13.8M/s 13.9M/s 15.7M/s 8.05M/s 10.4M/s 8.08M/s 11.5M/s 512B 7.07M/s 7.32M/s 7.32M/s 7.86M/s 4.32M/s 5.44M/s 4.21M/s 5.93M/s

$ sudo ./flashbench --open-au --erasesize=8388608 /dev/sda --blocksize=512 --open-au-nr=1 8MiB 103M/s 4MiB 77.5M/s 2MiB 106M/s 1MiB 106M/s 512KiB 106M/s 256KiB 88.6M/s 128KiB 99.6M/s 64KiB 102M/s 32KiB 90M/s 16KiB 88.8M/s 8KiB 88.9M/s 4KiB 58.3M/s 2KiB 16.5M/s 1KiB 11.8M/s 512B 6.72M/s

arnd@ocdc-kvm:~/git/flashbench$ sudo ./flashbench --open-au --erasesize=8388608 /dev/sda --blocksize=512 --open-au-nr=1 --offset=$[63 * 512] 8MiB 100M/s 4MiB 103M/s 2MiB 103M/s 1MiB 73.9M/s 512KiB 96.6M/s 256KiB 85.6M/s 128KiB 69.6M/s 64KiB 59.9M/s 32KiB 36.1M/s 16KiB 37.3M/s 8KiB 18.2M/s 4KiB 15.8M/s 2KiB 14.3M/s 1KiB 10.4M/s 512B 5.85M/s

arnd@ocdc-kvm:~/git/flashbench$ sudo ./flashbench --open-au --erasesize=8388608 /dev/sda --blocksize=512 --open-au-nr=1 --offset=4096 8MiB 102M/s 4MiB 106M/s 2MiB 87.4M/s 1MiB 92.6M/s 512KiB 104M/s 256KiB 99M/s 128KiB 88M/s 64KiB 90.7M/s 32KiB 92.9M/s 16KiB 96.3M/s 8KiB 79.9M/s 4KiB 53.1M/s 2KiB 14.7M/s 1KiB 10.9M/s 512B 6.17M/s

arnd@ocdc-kvm:~/git/flashbench$ sudo ./flashbench --open-au --erasesize=$[1024 * 1024] /dev/sda --blocksize=2048 --open-au-nr=64 1MiB 99.1M/s 512KiB 102M/s 256KiB 97.2M/s 128KiB 98.4M/s 64KiB 94.5M/s 32KiB 87.1M/s 16KiB 91.2M/s 8KiB 80.8M/s 4KiB 54.7M/s 2KiB 10.6M/s

arnd@ocdc-kvm:~/git/flashbench$ sudo ./flashbench --open-au --erasesize=$[1024 * 1024] /dev/sda --blocksize=2048 --random --open-au-nr=64 1MiB 102M/s 512KiB 97.5M/s 256KiB 96.3M/s 128KiB 95.8M/s 64KiB 89.2M/s 32KiB 89.6M/s 16KiB 83.7M/s 8KiB 82.8M/s 4KiB 53.8M/s 2KiB 11.3M/s

arnd@ocdc-kvm:~/git/flashbench$ sudo ./flashbench --open-au --erasesize=$[1024 * 1024] /dev/sda --blocksize=2048 --random --open-au-nr=64 --offset=4096 1MiB 97.5M/s 512KiB 98.8M/s 256KiB 99.4M/s 128KiB 94.6M/s 64KiB 91.3M/s 32KiB 89.5M/s 16KiB 90.3M/s 8KiB 82.5M/s 4KiB 55.3M/s 2KiB 11.3M/s

arnd@ocdc-kvm:~/git/flashbench$ sudo ./flashbench --open-au --erasesize=$[1024 * 1024] /dev/sda --blocksize=2048 --random --open-au-nr=64 --offset=2048 1MiB 92.2M/s 512KiB 91.2M/s 256KiB 78.7M/s 128KiB 69.1M/s 64KiB 44M/s 32KiB 32.5M/s 16KiB 23.8M/s 8KiB 15.8M/s 4KiB 10.9M/s 2KiB 11.2M/s