root@yama:/var/log# hdparm -tT /dev/sda

/dev/sda:
 Timing cached reads:   6968 MB in  2.00 seconds = 3486.94 MB/sec
 Timing buffered disk reads:  232 MB in  3.01 seconds =  77.18 MB/sec
root@yama:/var/log# hdparm -tT /dev/sdb

/dev/sdb:
 Timing cached reads:   7232 MB in  2.00 seconds = 3619.44 MB/sec
 Timing buffered disk reads:  178 MB in  3.02 seconds =  59.04 MB/sec
root@yama:/var/log# hdparm -tT /dev/sdc

/dev/sdc:
 Timing cached reads:   6398 MB in  2.00 seconds = 3201.29 MB/sec
 Timing buffered disk reads:  176 MB in  3.01 seconds =  58.38 MB/sec
root@yama:/var/log# hdparm -tT /dev/hda

/dev/hda:
 Timing cached reads:   6594 MB in  2.00 seconds = 3298.96 MB/sec
 Timing buffered disk reads:  156 MB in  3.02 seconds =  51.73 MB/sec