  The VERTEX code is employed for multi-dimensional neutrino-radiation
hydrodynamics simulations of core-collapse supernova explosions from first
principles. The code is considered state-of-the-art in supernova research and
it has been used for modeling for more than a decade, resulting in numerous
scientific publications. The computational performance of the code, which is
currently deployed on several high-performance computing (HPC) systems up to
the Tier-0 class (e.g. in the framework of the European PRACE initiative and
the German GAUSS program), however, has so far not been extensively documented.
This paper presents a high-level overview of the relevant algorithms and
parallelization strategies and outlines the technical challenges and
achievements encountered along the evolution of the code from the gigaflops
scale with the first, serial simulations in 2000, up to almost petaflops
capabilities, as demonstrated lately on the SuperMUC system of the Leibniz
Supercomputing Centre (LRZ). In particular, we shall document the parallel
scalability and computational efficiency of VERTEX at the large scale and on
the major, contemporary HPC platforms. We will outline upcoming scientific
requirements and discuss the resulting challenges for the future development
and operation of the code.
