Release Announcement

We are pleased to announce the sixth release (code name "Ørsted") of the Einstein Toolkit, an open, community developed software infrastructure for relativistic astrophysics. This release includes various improvements to the MHD handling within GRHydro, and improvements to the Cactus flesh. In addition, bug fixes accumulated since the previous release in May 2012 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 hydrodynamics code GRHydro (an updated and extended version of the public release of the Whisky code). 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 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 1212401/1212426/1212433/1212460, 0903973/0903782/0904015 (CIGR), and also by 0905046/0941653 (PetaCactus) and 0710874 (LONI Grid).

The Einstein Toolkit contain over 170 regression test cases. On a large portion of the tested machines, all of these testsuites pass, using both MPI and OpenMP parallelization.

The changes between this and the previous release include:

  • Compatibility

The following changes lead to potential different numerical results or the need to modify optionlists:
  • Cactus: Move MPI support from flesh to a thorn; use new MPI_DIR variable to control use of MPI (see below)
  • McLachlan: Correct some errors in CCZ4, in particular the GammaShift parameter
  • McLachlan: Change the default value of apply_dissipation to "never".

  • Changes since last release

  • GetComponents:
    • anonymous checkout is now used by default. Use --no-anonymous for authenticated checkouts
    • no longer use "shallow git clones" by default
  • simfactory
    • updates of various machine configurations
    • Replace large files by hard links during cleanup
    • Basic configuration file for Ubuntu, Debian and Fedora operating systems.
  • utils: syntax highlight for vim and emacs
  • Cactus flesh:
    • grid functions may be padded, i.e. the driver may allocate more grid points than requested. The allocated size of grid functions can be accessed using cctk_ash. Note however, that this can be different from cctk_lsh. The latter is that part (size) of cctk_ash that is used within a simulation, i.e. that was set as simulation size via parameters. This is necessary for vectorization where the size of arrays needs to be a multiple of some number, but the simulation domain might not be. There is no padding by default.
    • correctly detect circular schedule items
    • replace CCTK_RESTRICT by restrict, which is now defined by the flesh
    • Change per thorn -DTHORN_IS_xxx to a per thorn -I bindings/include/xxx
    • Correct error in determining dependencies
    • have -reconfig target execute -cleandeps after reconfiguration
    • add parameters to reverse un-enforced Cactus schedule ordering
    • Move MPI support from flesh to a thorn
    • Support various new Darwin minor versions
    • increase default value of RELTOL to 1e-12
    • Enforce that arrangement names are legal C identifiers
    • Update Fortran API for CCTK_LOOP macros
    • Add autoconf check whether C99 is supported (now required)
    • New option -P (--exit-after-param-check) to exit after param check
    • allow ${parfile} in parameter files to allow ${parfile}/subdir
  • Carpet
    • Now lives in git again
    • A parameter CarpetLib::interpolate_from_buffer_zones was introduced which, in order to get the correct behaviour (not to use the buffer zones for interpolations), should be set to "no". However, since this changes the way things had been done in the past and this change isn't well tested yet, the default is still "yes" (as like before the parameter was introduced). The default will very likely be changed for the next Einstein Toolkit release, after more testing.
    • Added "balanced" domain decomposition
    • Update setting CPU affinity
    • change defaults of periodic_[xyz] to "yes" to match PUGH
    • CarpetIOHDF5: add option checkpoint_every_divisor
    • CarpetIOHDF5: teach the checkpointer to write index files
    • CarpetIOHDF5: add support for index files to file reader
    • LoopControl: Change printstats default to "no"
    • CarpetInterp2: New ENO2 interpolator.
    • Support more than one hierarchy of timers
    • Add timers for refinement levels
    • CarpetLib: Support higher-then 2nd order restriction operator for cell-centered meshes for Langrange prolongated grid functions.
  • EinsteinExact: New arrangement, to eventually replace the Exact thorn. The thorns in this arrangement are generated by Kranc
  • McLachlan
    • Correct some errors in CCZ4, in particular the GammaShift parameter
    • Change the default value of apply_dissipation to "never".
  • ExternalLibraries: MPI is now treated like any other library on which flesh and thorns may depend, such as e.g. the GSL. It is thus configured via thorn ExternalLibraries/MPI, and not via the flesh any more. In particular, the option "MPI = ..." does not work any more and must not be used; instead, use e.g. "MPI_DIR = " to point to an existing installation. You may also say "MPI_DIR = BUILD" to have Cactus build OpenMPI automatically, which is a convenient way of using MPI on a system where it may not be installed.
  • LocalInterp: The interpolation loop uses OpenMP
  • MoL: add multirate capabilities and three new multirate rk schemes
  • SphericalSurface: make maxnphi and maxntheta parameters steerable
  • NaNChecker: Add options to use restriction mask to ignore unused points, output more information about the failed points, use OpenMP during NaN check
  • Multipole: Implement Driscoll&Healy integration
  • HydroBase: schedule hydrobase_InitExcisionmask global-early loop-local
  • TmunuBase: support_old_CalcTmunu_mechanism is now deprecated and is likely to be removed soon
  • EOS_Omni: make more parameters steerable, add option read_table_on_single_process to have a named processor read the full table and MPI_Bcast it to the other processors
  • GRHydro
    • C2P: resort to bisection if Newton-Raphson fails. This is only activated if user requested this
    • introduce parameters GRHydro_Y_e_min and GRHydro_Y_e_max to fix issues with EOS tables that don't extend sufficiently far
    • Fixes to atmosphere mask and the way we sync
    • various fixes to ePPM
    • Option to use the slow sector of multirate RK methods
    • fixed issues with hot EOS treatment
    • Option to reconstruct W*vel instead of vel
    • use an early atmosphere reset to ensure past timelevels are initialized correctly
    • various MHD fixes
  • Exact: openmp fixes
  • GRHydro_InitData: new poloidal magnetic field routine, Added option to smooth metric inside horizon, Alfven wave test
  • SummationByParts: improve OpenMP parallelization
  • PITTNull*: respect Cactus' IO::truncate parameter
  • AEIThorns/Trigger now part of the Einstein Toolkit External libraries:
  • MPI: new - use this instead of the flesh mechanism (see above)
  • BLAS: update to 3.4.2
  • FFTW3: update to 3.3.2
  • HDF5: will likely not build fortran and C++ api for next release by default (but still does now)
  • LAPACK: update to 3.4.2
  • LORENE: don't use OpenMP unless it's enabled within Cactus
  • OpenSSL: improve search for existing library
  • zlib: update to 1.2.7
  • hwloc: new thorn for libhwloc

  • How to upgrade from Lovelace (ET_2012_05)

To upgrade from the previous release, use GetComponents with the new thornlist to check out the new version. Due to the change of Carpet repository type, using GetComponents to upgrade a Lovelace checkout is unlikely to work.

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

  • Remaining issues with this release

  • Certain machines need to be configured specially in Simfactory because the remote directories cannot be determined automatically just from the username. See the Machine notes below.
  • CarpetIOHDF5: When the new parameter CarpetIOHDF5::output_symmetry_points is set to "yes", then symmetry points are not actually output if CarpetIOHDF5::output_buffer_points has been set to "no".
  • Recovering with Carpet: The maximum number of timelevels that can be recovered is Carpet::prolongation_order_time+1. This is usually the case, but it is possible to write parameter files e.g. with prolongation_order_time=1 that use 3 timelevels. This bug manifests in an assert() failure when recovering from checkpoints. The work-around is to either increase Carpet::prolongation_order_time or decrease the number of timelevels for the grid function in question accordingly.

  • Machine notes

  • Kraken: defs.local.ini needs to have sourcebasedir = $HOME configured for this machine. You need to determine $HOME by logging in to the machine.
  • LoneStar and Ranger: 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.
  • Pandora: The LSU system pandora has at the time of writing not only severe problems of compiling Cactus (can crash the filesystem), but in part due to this also outstanding are some failing testsuite results. Please contact Peter Diener at CCT (LSU) before trying to use this machine.

All repositories participating in this release carry a branch ET_2012_11 marking this release. These release branches will be updated if severe errors are found.

The "Ørsted" Release Team on behalf of the Einstein Toolkit Consortium (2012-11-08)

   Eloisa Bentivegna
   Tanja Bode
   Peter Diener
   Roland Haas
   Ian Hinder
   Frank Löffler
   Bruno Mundim
   Christian D. Ott
   Erik Schnetter

November 8, 2012