Charm++ mini-applications

Mini-applications that show how Charm++ programs are structured at a larger scale than the programs in examples/, and that serve as benchmarks and as stress tests of the runtime. They are described at https://charmplusplus.org/miniApps/.

directory	what it is
charm++/amr	mesh restructuring for adaptive mesh refinement
charm++/barnes	Barnes-Hut N-body (needs the structures library from ChaNGa)
charm++/charmlu	dense LU solver, from the HPC Challenge (needs BLAS and LAPACK)
charm++/fft-trans	1D FFT with three all-to-all transposes (needs FFTW3)
charm++/hpccg	HPCCG conjugate gradient, from the Mantevo suite
charm++/hpccstream	HPC Challenge STREAM (EP Stream)
charm++/kripke	LLNL's Kripke, a proxy for Sn particle transport
charm++/leanmd	molecular dynamics with the Lennard-Jones potential
charm++/randomAccess	HPC Challenge RandomAccess
charm++/triangularsolver	solver for sparse triangular systems

Each was imported with its history from the repository of the same name under https://github.com/UIUC-PPL in November 2026. The imported commits keep their original paths, so git log -- charm++/<name> shows only the import merge; git log <merge>^2 shows the history before it. Charm++'s own examples/charm++/leanmd is an older, simpler version of LeanMD.

Building and testing

The Makefiles expect to sit in a Charm++ build directory, at <build>/miniapps/charm++/<name>, and find charmc and testrun there. Charm++ includes this repository as a git submodule at miniapps/, which a plain clone does not fetch. To use it:

git submodule update --init miniapps     # in the charm source tree
make -C <build>                          # mirrors miniapps/ into the build directory
make -C <build>/tmp test-miniapps        # or: make -C <build>/miniapps test

make test in a mini-application's directory runs its short test; the ones that need an external library skip when it is missing.

Licenses

Everything here is under the Charm++ license (LICENSE, the Apache License 2.0, as for Charm++ itself), except:

• charm++/hpccg: the files carrying the Sandia Corporation copyright are under the GNU Lesser General Public License, version 2.1 or later (charm++/hpccg/COPYING.LESSER).
• charm++/kripke: a Charm++ port of LLNL's Kripke, under the BSD 3-Clause License (charm++/kripke/LICENSE).
• charm++/hpccstream/MPIStream: John D. McCalpin's STREAM, under the license in the header of stream.c, which includes conditions on publishing results.

The external libraries that charmlu (BLAS, LAPACK), fft-trans (FFTW3) and barnes (ChaNGa's structures) need are not part of this repository; build against the system's copies.