Dom0:

hdparm -tT /dev/md1

/dev/md1:
 Timing cached reads:   1720 MB in  2.00 seconds = 860.13 MB/sec
 Timing buffered disk reads:  234 MB in  3.00 seconds =  77.98 MB/sec


DomU:

hdparm -tT /dev/xvda

/dev/xvda:
 Timing cached reads:   1640 MB in  2.00 seconds = 819.82 MB/sec
 Timing buffered disk reads:  224 MB in  3.00 seconds =  74.62 MB/sec