sudo hdparm -Tt /dev/sda
[sudo] hajzer jelszava:

/dev/sda:
 Timing cached reads:   2534 MB in  1.99 seconds = 1270.20 MB/sec
 Timing buffered disk reads: 1428 MB in  3.04 seconds = 470.30 MB/sec


sudo hdparm --direct -Tt /dev/sda

/dev/sda:
 Timing O_DIRECT cached reads:   810 MB in  2.00 seconds = 405.83 MB/sec
 Timing O_DIRECT disk reads: 1152 MB in  3.00 seconds = 383.42 MB/sec