Release Announcement

We are pleased to announce the fifteenth release (code name "Hack") of the Einstein Toolkit, an open, community developed software infrastructure for relativistic astrophysics. The highlights of this release are:

  • The new Piraha parser now parses all CCL and parameter files. The only user-visible change should be improved error messages.
  • A much more general, piece-wise EoS for EOS_Omni and the corresponding improvements for neutron star initial data using the Lorene library

In addition, bug fixes accumulated since the previous release in December 2016 have been included.

The Einstein Toolkit is a collection of software components and tools for simulating and analyzing general relativistic astrophysical systems that builds on numerous software efforts in the numerical relativity community including CactusEinstein, the Carpet AMR infrastructure and the relativistic magneto-hydrodynamics code GRHydro. For parts of the toolkit, the Cactus Framework is used as the underlying computational infrastructure providing large-scale parallelization, general computational components, and a model for collaborative, portable code development. The toolkit includes modules to build complete codes for simulating black hole spacetimes as well as systems governed by relativistic magneto-hydrodynamics.

The Einstein Toolkit uses a distributed software model and its different modules are developed, distributed, and supported either by the core team of Einstein Toolkit Maintainers, or by individual groups. Where modules are provided by external groups, the Einstein Toolkit Maintainers provide quality control for modules for inclusion in the toolkit and help coordinate support. The Einstein Toolkit Maintainers currently involve postdocs and faculty from six different institutions, and host weekly meetings that are open for anyone to join in.

Guiding principles for the design and implementation of the toolkit include: open, community-driven software development; well thought out and stable interfaces; separation of physics software from computational science infrastructure; provision of complete working production code; training and education for a new generation of researchers.

For more information about using or contributing to the Einstein Toolkit, or to join the Einstein Toolkit Consortium, please visit our web pages at

The Einstein Toolkit is primarily supported by NSF 1550551/1550461/1550436/1550514 (Einstein Toolkit Community Integration and Data Exploration).

The Einstein Toolkit contains about 200 regression test cases. On a large portion of the tested machines, almost all of these test suites pass, using both MPI and OpenMP parallelization.

The changes between this and the previous release include:

Larger changes since last release

  • Cactus Flesh
    • The flesh now provides capability CACTUS with the respective Cactus version string for thorns to possibly depend upon.
    • In verbose build mode, Cactus now outputs time stamps.
    • Fix building Cactus using new versions of Perl.
    • Piraha now parses all CCL files by default. The old parser is still present, but disabled by default. This includes new (more descriptive) error messages.
  • MoL
    • Support integrating grid scalars, and grid arrays with RK operators
  • Simfactory
    • Updates to several machines (too many to list)
  • CarpetIOHDF5
    • add option to have one output file per process
  • GetComponents
    • Process git repositories in parallel (when requested)
  • EOSOmni
    • Support piece-wise polytropic EoS with up to 10 pieces
  • NewRad
    • Support for Llama outer boundary
  • Meudon_Bin_NS
    • Now uses EOS_Omni, and with that is able to use more EoSs
    • Bugfix: earlier versions set a wrong atmosphere for EoS-Gamma!=2. However, depending on evolution settings those might have been overwritten with the (correct) values later.
    • Generate binaries necessary to not only read, but also generate Lorene binary neutron star initial data
    • Make this thorn work with older and current Lorene libraries (e.g., both Lorene thorns)
  • ML_ADMConstraints
    • Workaround for otherwise wrong results when using the Intel compiler version 15 and up.
  • PITTNullCode
    • Bug fix for calculating J.

New thorns or tools

    • A current version of Lorene was packaged as LORENE2. Initial data files are not comparible with those of the older LORENE thorn, and the API for codes using LORENE also changed. Due to this, only one of these thorns can be compiled into a Cactus executable, which for this release is still the older thorn LORENE.

Upcoming changes for the next releases

The Tmunu parameter support_old_CalcTmunu_mechanism, will be removed after this release. If you rely on this, your code is probably unnecessarily slow. Let us know if the removal would create a problem for you.

Most of the Fortran code in GRHydro was already replaced by more modern, and much easier to maintain C++ code. Up to now, both versions are compiled, and can be chosen at start-time. For a few releases the C++ versions are the default. After this release, the Fortran versions will be removed. Let us know if the removal would create a problem for you.

How to upgrade from Payne-Gaposchkin (ET_2016_11)

To upgrade from the previous release, use GetComponents with the new thornlist to check out the new version.

See the Download page on the Einstein Toolkit website for download instructions.

Machine notes

Supported (tested) machines include:

  • Default Debian, Ubuntu, Fedora, CentOS, and MacOS installations
  • Bethe
  • Bluewaters
  • Comet (#)
  • Cori
  • Draco
  • Edison
  • Galileo
  • Gulob
  • Hydra
  • Marconi
  • Minerva
  • Queenbee 2
  • Supermike II
  • Wheeler
  • Zwicky
  • TACC machines: defs.local.ini needs to have sourcebasedir = $WORK and basedir = $SCRATCH/simulations configured for this machine. You need to determine $WORK and $SCRATCH by logging in to the machine. A new configuration for KNL nodes is being worked on, but not yet included in the release (but compilation works and tests mostly pass).
  • (#) On Comet, using more than one MPI process might produce corrupt output files. This is a known file system bug on this machine.

All repositories participating in this release carry a branch ET_2017_06 marking this release. These release branches will be updated if severe errors are found.

The "Hack" Release Team on behalf of the Einstein Toolkit Consortium (2017-07-17)

   Eloisa Bentivegna
   Steven R. Brandt
   Peter Diener
   Roland Haas
   Ian Hinder
   Frank Löffler
   Roberto De Pietri
   Erik Schnetter
   Yosef Zlochower

July 17th, 2017