Welcome to openQCD-FASTSUM, an extension of the renowned openQCD 1.6 lattice QCD code developed by members of the FASTSUM lattice collaboration.

openQCD-FASTSUM has all of the capabilities of openQCD but implements two new features

  • Anisotropic actions
  • Stout smearing

Getting started

Downloading the source

The source code is available on GitLab where one can either clone the repository or download a pre made zip.

Download v1.0

To clone the GitLab repository

git clone https://gitlab.com/fastsum/openqcd-fastsum.git

This has the added benefit that the program logfile will contain a git SHA which can later be used to reference which version of the code the results were generated with.

In this repository the master branch points to the latest release while the devel branch contains the most up to date (possibly broken) version. The individual releases are also tagged e.g. v1.0.


To build the code one can simply run make in the build directory:

cd build

However, one probably wants to configure the build prior to this by editing the compile_settings.txt file. It is also possible to copy the build directory elsewhere if one wishes to keep multiple builds. For information on how the build system works, which targets are available, and which flags are supported, please see the build documentation.

Configuring the action

The openQCD-FASTSUM code is compatible with all openQCD 1.4 and 1.6 configurations and accept the following additional (optional) blocks


[Anisotropy parameters]
use_tts       0
nu            1.5
xi            4.3
cR            1.5
cT            0.9
us_gauge      0.7
ut_gauge      1.0
us_fermion    1.0
ut_fermion    1.0

Stout smearing

[Smearing parameters]
n_smear       2
rho_s         0.14
rho_t         0.00
gauge         0
fermion       1

For more information on how the parameters are defined, please see the documentation.

Bugs and issues

If you find any bugs please report them to the repository issue tracker

Register new issue

Here you can also see known bugs and hopefully get a sense of its status. You can also send us an email with the issue you are having.

Authors and License

openQCD-FASTSUM is developed by Jonas Rylund Glesaaen and Benjamin Jäger, and licensed under the GNU Public License (GPL).

openQCD 1.6 was developed by Martin Lüscher and Stefan Schaefer with contributions from others (see homepage, also GPL license).

openQCD-FASTSUM also include optimisations for BlueGeneQ developed by Dalibor Djukanovic, Mauro Papinutto, and Hubert Simma, as well as additional AVX512 vectorisation instructions developed by Michele Messiti and Jarno Rantaharju of the SA2C.