Migrating from Sparc/Solaris to x86/Linux
This is an introduction to setting up your account on our systems. When first logging in, you are presented with a default set-up that enables the use of basic system commands, simple compilers, and access to the scheduler. This help file is meant to explain how to modify that default.
The login node for the Linux nodes is swlogin1. It may be accessed in two different ways:
For people used to work on sflogin0, this iomplies an additional "node hop" to swlogin1.
There are several set-up files in your home directory:
Most of the setup is automatic through usepackage. On login, you have a default setup that is appropriate for a Linux system. Additional packages can be set up by adding commands such as
to the above setup files, if you want to use the Python 3 distribution "Anaconda" (as an example). Note that this is the same as it was on Solaris, but that the available packages may differ. For a list, use the
The standard Fortran/C/C++ compilers differ between the Solaris and the Linux systems. The ones on the x86/Linux platform are discussed here. Here is a comparison in table form. Since there are two compilers (gnu and Intel) on the Linux platform, they are treated separately. The default is gnu. We also list the MPI - related commands for setup, compilation, and runtime.
Note that all programs that were running on the Solaris platform have to be re-compiled on Linux. Binaries are not compatible as they are based on different instruction sets.
On both Solaris and Linux systems, the MPI distribution used is OpenMPI. On the Solaris platform this was integrated with the standard Studio compilers. On the Linux platform, two versions are in use:
All of these versions use the mpirun command to invoke the runtime environment. Check with which mpirun to see which version you are currently using.
Important: Some programs use binary format for data I/O. These files are likely not compatible between the two platforms, which means that it may be necessary to re-run the programs on the new platform or convert the data files before using them. This is due the different "Endianness" on the two platforms: Sparc/Solaris is big-Endian and x86/Linux is little-Endian. If you encounter issues with data files, please get in touch with us.
How do I run parallel code ?
That depends on how the code is "parallelized":
You can learn more about parallel code by having a look at our Parallel Programming FAQ. We also have a bit more specific information about parallel programming tools, namely OpenMP compiler directives and the Message Passing Interface (MPI).
If you have questions that you can't resolve by checking documentation, email to email@example.com.