The 2-processor system ``gunnar'' from Hewlett-Packard is a dual Itanium 2 machine with two 900MHz ia64 CPU modules, 4GB of RAM and 70GB user disk space.
The single-processor performance of CO5BOLD is very good. On two processor the code runs even faster but just stops after a few time steps. The number of time steps varies even for simulations with the very same start model and parameter file. Therefore, OpenMP should not be activated currently.
The compiler settings are somewhat similar to the settings of the HP V2500 system in Section 4.6.3:
+U77: Link proper library to make the machine understand e.g.tex2html_verb_mark>635
+cpp=yes: Switch on the C preprocessor. Note that all Fortran90 files have to end with ``.f90''. The ``.F90'' suffix does not seem to work.
+Ofast: High optimization level. And
+Ofasteris even higher.
+Oopenmp +Onoautopar: Try to enable parallelization with OpenMP directives, disable auto-parallelization. The code compiles and runs fast but crashes after a few time steps.
A proposed compiling sequence is (LHDrad, DUST, MHD do not compile):