Using the Altix UV 100 system

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The SGI system is used for very specific applications (in need of a large and highly performant shared-memory system) and can presently only be accessed by the Theoretical Chemistry group. Entitled users may login to the system via ssh (the same rules as for the login nodes of the main system apply, i.e. access is only possible from within the intranet of the University, otherwise you have to establish a VPN tunnel):

The Altix UV system has a RHEL 6.0 operating system installed. As for the IBM cluster, the modules environment is used.

Compiling and linking applications

It is strongly recommended to use MPT (Message Passing Toolkit), SGI's own implementation of the MPI standard. It is only then that the highly specialized HW architecture of the system can be fully exploited. The MPT module must be loaded both for compiling and (in general) at runtime in order for you application to find the dynamically linked libraries:

module load mpt

Note that MPT is not a compiler. SGI does not provide own compilers for x86-64 based systems. One may, e.g., use the Intel compiler:

module load intel/ics

Basically, you can use the compiler the same way you are accustomed to, and link against the MPT library by setting the flag -lmpi. See the documentation provided below, and also for how to run MPI programs.

Submitting SGE jobs

Only entitled users can submit jobs to the SGI Altix UV system (the jobs of other users would never start). For a job that is to execute on the UV100 system, your SGE job submission script must contain the line

#$ -l uv100=true

From SGE's point of view, the system is treated as a single, big SMP node with 120 cores, 630 GB of main memory available for running jobs, and 11 TB of scratch disk space. So far only the parallel environment smp is configured on the system.


(Both of the above are also available as PDF download.)