Running on the Altix (Newton)

Standard Batch Work

Newton is now configured as a 512 processor single system image machine, running a single copy of the operating system, visible to the outside world as newton.cfs.ac.uk. The user has 128, 1.5GHz processors and 374, 1.3GHz processors available for batch work, hence a maximum job size of 502 processors. During core hours, the development queue will take up 16 of the 1.3GHz processors. Therefore since jobs over 358 processors will have to span the two types of processor, they will initially only be run by special request to csar-advice@cfs.ac.uk . Users must submit jobs to the newt15 queue in order to run on the faster 1.5GHz processors. You will need to add the following line to your batch script:

#BSUB -q newt15

Please note that usage of these processors is charged at 10% above the 1.3 GHz processor rate. No job will run across both 1.3 GHz and 1.5GHz processors unless it is too large to be run without doing so.

Earlier configurations of Newton necessitated the use of the pam command for running MPI jobs. This command is no longer available, and all MPI jobs must be started using mpirun

Example 1

As an example, if we wish to submit a 128 processor MPI job to newton running for 1 hour then the following script would do the job

# Any environment variables you might
# want to set for your MPI job

You would then submit this job by typing the following at the command line
bsub < scriptname

where the < is essential.

Example 2

For OpenMP jobs, a script for a 16 processor job might look like this

You would then submit this job by typing the following at the command line
bsub < scriptname

where the < is essential.

For SHMEM jobs you should submit them in the same way as for MPI jobs, but you should also set the environment variable NPES in your script.