Description:

fio is an I/O tool meant to be used both for benchmark and
stress/hardware verification.
It has support for 9 different types of I/O engines
(sync, mmap, libaio, posixaio, SG v3, splice, null, network, syslet),
I/O priorities (for newer Linux kernels), rate I/O, forked or threaded jobs,
and much more. It can work on block devices as well as files.
fio accepts job descriptions in a simple-to-understand text format.
Several example job files are included.
fio displays all sorts of I/O performance information.
It supports Linux, FreeBSD, and OpenSolaris.