USBRaid speedtest

root@SanMan:~# dd if=/dev/zero of=tempfile bs=1M count=1024 conv=fdatasync,notrunc
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 39.3647 s, 27.3 MB/s
root@SanMan:~# echo 3 > /proc/sys/vm/drop_caches
root@SanMan:~# dd if=tempfile of=/dev/null bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 16.913 s, 63.5 MB/s.
root@SanMan:~# dd if=tempfile of=/dev/null bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 0.171533 s, 6.3 GB/s
root@SanMan:~#