History

Cactus is a direct descendant of many years of code development in Ed Seidel's group of researchers at the National Center for Supercomputing Applications (NCSA) as the group wrestled to numerically solve Einstein's Equations for General Relativity and thus model black holes, neutron stars and boson stars.

In 1995, Ed Seidel and many of his group moved to the Max Planck Institute for Gravitational Physics (Albert Einstein Institute or AEI) in Potsdam, Germany. Frustrated by the difficulties of coordinating the development and use of several different codes across a large collaborative group, Paul Walker, Joan Masso, Ed Seidel, and John Shalf, designed and wrote the original version of Cactus, Cactus 1.0, which provided a collaborative parallel toolkit for numerical relativity.

As Cactus was used over the next years for research in Numerical Relativity, it was realized that we could easily rewrite the code in such a way that it could be used not just by numerical relativists, but also by other computational scientists in other domains with similar needs for large scale computing. This lead to a major redesign and rewrite of Cactus, learning from all our previous experiences. In July 1999 Cactus 4.0 Beta 1 was finally released, with the main development coming from Tom Goodale, Joan Masso, Gabrielle Allen, Gerd Lanfermann and John Shalf.

We are (unfortunately) still on the Cactus 4.0 release cycle, but lots has happened since 1999. Cactus has been adopted not just by application developers, but also by computer science researchers, and has been involved in many prize winning efforts for large scale computing, grid computing and high speed networks. More information about these awards can be found on our News pages.

In 2003, several members of the AEI Cactus group left Germany to help found the Center for Computation & Technology (CCT) at Louisiana State University with new director Ed Seidel. Cactus is now developed and supported by a close-knit team spanning AEI and CCT.

Along the way, many other friends and colleagues have contributed to Cactus, including Wai-Mo Suen, Thomas Dramlitsch, Thomas Schweizer, Karen Camarda, Malcolm Tobias, Mark Miller, Ed Evans, Werner Benger, Bernd Brügmann, Ian Hawke, Andre Merzky, and Bernard Schutz.

Funding

• Max-Planck-Gesellschaft
• Center for Computational & Technology at LSU
• National Center for Supercomputing Applications
• Lawrence Berkeley National Laboratory
• Washington University
• University of Tübingen

• NSF Astrophysics Simulation Collaboratory: Enabling Large Scale Simulations of Relativistic Astrophysics (NSF PHY-9979985)
• European Commission Theoretical Foundations of Sources of Gravitational Waves in the Next Century: Synergy between Supercomputer Simulations and Approximation Techniques (HPRN-CT-2000-00137)
• DFN-Verein GriKSL: Grid-Immersion: Kollision Schwarzer Loecher (TK 6-2-AN 200)
• European Commission GridLab: A Grid Application Toolkit and Testbed (IST-2001-32133)
• DFG Gravitational Wave Astronomy and Sources of Gravitational Waves (SRB/TR 7)
• DFN-Verein TiKSL: Tele Immersion: Collision of Black Holes
• DDDAS-TMRP DynaCode: A General DDDAS Framework with Coast and Environment Modeling Applications

• NSF Louisiana's Research Infrastructure Improvement Strategy (CyberTools) (NSF 0701491)
• NSF XiRel: Next Generation Infrastructure for Numerical Relativity (NSF )
• NSF Alpaca: Cactus Tools for Application Level Profiling and Correctness Analysis (NSF 0701566)
• ONR Development of an Integrated Modeling Framework for Simulations of Coastal Processes in Deltaic Environments Using High-Performance Computing (COMI)
• DOE/BOR Ubiquitous Computing and Monitoring System for Discovery and Management of Energy Resources (UCOMS) (DOE DE-FG02-04ER46136, BOR DOE/LEQSF(2004-07))