stress is a workload generator and stress tester for Unix-like systems. It will impose user-specified amounts of CPU, I/O, RAM, and HDD load and report any errors it detects. It is used for automated stress testing and for debugging system components that fail only or more often when under load. It runs on x86, PPC64, and PPC 32 GNU/Linux, Tru64, SPARC Solaris, and other platforms.
