fio is an I/O tool meant to be used both for benchmark and stress/hardware
verification. It has support for 13 different types of I/O engines (sync,
mmap, libaio, posixaio, SG v3, splice, null, network, syslet, guasi,
solarisaio, and more), 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. Fio is in wide use in many places, for both
benchmarking, QA, and verification purposes. It supports Linux, FreeBSD,
NetBSD, OS X, OpenSolaris, AIX, HP-UX, and Windows.


Example Usage:

This process runs a random read and write of two 128MB files created during
execution of fio.

$ fio --name=global --rw=randread --size=128m --name=job1 --name=job2