Something

BEFORE

/dev/md0:
 Timing cached reads:   4208 MB in  2.00 seconds = 2104.59 MB/sec
 Timing buffered disk reads:  566 MB in  3.01 seconds = 187.99 MB/sec

AFTER

/dev/md0:
 Timing cached reads:   4048 MB in  2.00 seconds = 2024.25 MB/sec
 Timing buffered disk reads:  698 MB in  3.01 seconds = 232.09 MB/sec