COMSOL can run a job on many cores in parallel (Shared-memory processing or multithreading) and on many physical nodes (distributed computing through MPI). A good strategy is to use both parallel operations to maximize parallelization benefits. This means that you should request some cores on a certain number of nodes to leverage Comsol parallelization features. Cluster computing requires a floating network license (provided by POLIMI).

1. Submit cluster-enabled batch job via PBS script - Requires completed and saved model mph file
2. Branch off cluster-enabled batch jobs from the COMSOL GUI process started on masternode - Allows GUI model work, and batch job submission to PBS from within the GUI; limited command-line proficiency needed; with the Cluster Sweep feature it is possible to submit a single batch job from the COMSOL GUI and continue working in the GUI while the cluster job is computing in the background.
3. Start a cluster-enabled COMSOL desktop GUI on the masternode and work interactively with cluster jobs
4. Start the COMSOL Desktop GUI as a client on a local PC or Mac and connect to a cluster-enabled COMSOL server on the masternode and work interactively

Actually we support only method 1 and 2.

The command to set the Comsol environment is: module load comsol/5.3.0

The link to the documentation is: http://masternode.chem.polimi.it/comsol53

#!/bin/bash
#
# Set Job execution shell
#PBS -S /bin/bash
 
# Set Job name: <jobname>=jobcomsol 
#PBS -N jobcomsol
 
# Set the execution queue: <queue name> is one of 
# gandalf, merlino, default, morgana, covenant
#PBS -q <queue name>
 
# Set mail addresses that will receive mail from PBS about job
# Can be a list of addresses separated by commas (,)
#PBS -M <polimi.it or mail.polimi.it email address only>
 
# Set events for mail from PBS about job
#PBS -m abe
 
# Job re-run (yes or no)
#PBS -r n
 
# Set standard output file 
#PBS -o jobcomsol.out
 
# Set standard error file 
#PBS -e jobcomsol.err
 
# Set request for nodes,number of cpu (cores),number of mpi processes per node
#PBS -l select=N:ncpus=C:mpiprocs=P
 
# Pass environment to job
#PBS -V
 
# Change to submission directory
cd $PBS_O_WORKDIR
 
# Command to launch application and it's parameters
 
module load comsol/5.3.0
 
export inputfile="<name-of-model-input-mph-file>.mph"
export outputfile="<name-of-output-mph-file>.mph"
 
echo "---------------------------------------------------------------------"
echo  "---Starting job at: `date`"
echo
echo "------Current working directory is `pwd`"
np=$(wc -l < $PBS_NODEFILE)
echo "------Running on ${np} processes (cores) on the following nodes:"
cat $PBS_NODEFILE
echo "----Parallel comsol run"
comsol -clustersimple batch -mpiarg -rmk -mpiarg pbs -inputfile $inputfile -outputfile
 $outputfile -batchlog jobcomsol.log
echo "-----job finished at `date`"
echo "---------------------------------------------------------------------"

Please report new interesting or broken links to clusterhpc-dcmc@polimi.it

The PARDISO Solver Project PARallel sparse Direct and multi-recursive Iterative linear SOlvers integrated in Comsol.

SParse Object Oriented Linear Equations Solver

A quick and clear guide on how to prepare the MPH input file for cluster processing

Hybrid parallel simulationa solutions with comsol on intel multicore and HPC clusters

Parallel Performance Studies for COMSOL Multiphysics Using Scripting and Batch Processing