Github: https://github.com/cxcv/iops

iops is an IO benachmark tool that performs random reads on block devices. If an exact block size is not specified using -b, the the size starts with the physical sector size (defaulting to 4k) and doubles every iteration of the loop. You can switch the read pattern using -p toggle.

./iops /dev/xvda1
/dev/xvda1, 107.37 G, sectorsize=512B, #threads=32, pattern=random:
 512  B blocks:  637.4 IO/s, 326.3 kB/s (  2.6 Mbit/s)
   1 kB blocks:  443.1 IO/s, 453.8 kB/s (  3.6 Mbit/s)
   2 kB blocks:  432.6 IO/s, 885.9 kB/s (  7.1 Mbit/s)
   4 kB blocks:  295.3 IO/s,   1.2 MB/s (  9.7 Mbit/s)
   8 kB blocks:  313.7 IO/s,   2.6 MB/s ( 20.6 Mbit/s)
  16 kB blocks:  295.5 IO/s,   4.8 MB/s ( 38.7 Mbit/s)
  32 kB blocks:  196.2 IO/s,   6.4 MB/s ( 51.4 Mbit/s)
  65 kB blocks:  167.0 IO/s,  10.9 MB/s ( 87.6 Mbit/s)
 131 kB blocks:   45.1 IO/s,   5.9 MB/s ( 47.3 Mbit/s)
 262 kB blocks:   50.8 IO/s,  13.3 MB/s (106.4 Mbit/s)
 524 kB blocks:   26.5 IO/s,  13.9 MB/s (111.1 Mbit/s)
   1 MB blocks:   25.0 IO/s,  26.2 MB/s (209.8 Mbit/s)
   2 MB blocks:    9.6 IO/s,  20.1 MB/s (161.1 Mbit/s)
   4 MB blocks:   13.2 IO/s,  55.4 MB/s (443.3 Mbit/s)
   8 MB blocks:    6.1 IO/s,  50.8 MB/s (406.4 Mbit/s)