fio is an I/O tool meant to be used both for benchmark and stress/hardware verification. It has support for 12 different types of I/O engines (sync, mmap, libaio, posixaio, SG v3, splice, null, network, syslet, guasi, 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. It supports Linux, FreeBSD, and OpenSolaris.
fio is extremely flexible and can be control IO in almost any fashion.
These details are provided for information only. No information here is legal advice and should not be used as such.