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How to Use the Razor Cluster

This is a brief “how to” summary of usage for users of the Razor cluster.

Razor has several partitions: Razor I (128 12-core nodes, dual X5670 processor, 24GB memory except 4 nodes have 96GB), Razor II (112 16-core nodes, dual E5-2670 processor, 32GB memory), and 10 large-memory four-socket nodes, some condo, of 256GB-3024GB memory. There is also a condo partition Razor III (64 16-core nodes, dual E5-2650V2 processor, 64GB memory) which will move to the Trestles cluster. Each node has a local hard drive with 900-1800GB usable for temporary space in /local_scratch/$USER/. Nodes are interconnected with QLogic QDR Infiniband. Operating system is Centos 6.5.

Parallel file systems are GPFS /storage/$USER and /scratch/$USER. Your home area is located at /gpfs_home/$USER and is autohomed to /home/$USER. The storage page explains storage policies and how to use different storage areas for different purposes.

Login node is razor.uark.edu which is a load balancer to identical login nodes with local names razor-l1 through razor-l3. If you have a UArk ID, you will use UArk login and password. AHPCC doesn't see, know, reset, or email UArk passwords: use UITS facilities password.uark.edu to reset. If you don't have a UArk ID, we will send you login ID and password on a secure web server.

The main production queues, with 6 and 72 hour walltime limits respectively, are tiny12core and med12core on Razor I and tiny16core and med16core or Razor II. Both systems also have quick-turnaround non-production 30-minute limit debug12core and debug16core. On Razor I only there is a serial12core queue for single-core jobs of 2GB or less memory, which runs up to twelve jobs on a single node. There are a number of special-purpose and condo queues documented in queues.

A sample Maui/Torque job script follows. This requests two 12-core nodes for 6 hours in the tiny12core queue. The job starts and runs in the submit directory ($PBS_O_WORKDIR) and uses every core available in the requested nodes for MPI NP=$(wc -l < $PBS_NODEFILE), or nodes*ppn=24 cores in this case. The MPI executable was previously compiled with Intel compiler version 14.0.3 and Intel MPI version 5.1.1 (see modules).

#PBS -N example1
#PBS -q tiny12core
#PBS -j oe
#PBS -m ae
#PBS -o zzz.$PBS_JOBID.tiny
#PBS -l nodes=2:ppn=12,walltime=6:00:00
module purge
module load intel/14.0.3 impi/5.1.1
cd $PBS_O_WORKDIR 
NP=$(wc -l < $PBS_NODEFILE)
mpirun -np $NP -machinefile $PBS_NODEFILE  ./mympiexecutable
razor_usage.txt · Last modified: 2016/06/15 16:59 by root