LIKWID is a tool suite for performance-oriented programmers offering command line tools for system topology, CPU/task affinity, hardware performance monitoring, micro-benchmarking and more. Besides the command line tools tools, almost all functionality is provided as a C library to be integrable in other tools. LIKWID is internationally widely used by many programmers for code modernization and computing centers for performance engineering and system monitoring. The easy-to-use interface with validated event sets plus derived metrics offers valuable input for users.
C/C++, Fortran, Lua, Python (pylikwid), Java (http://tiny.cc/p7pdez)
Open source: GPLv3