==== Environment Modules, .bashrc ====
==Modules==
When multiple versions of software are installed, some method is needed to use the version you want to use. The
[[http://modules.sourceforge.net/|Modules]] package is the overwhelming choice of HPC centers for this.
Modules is supplied on the system to manipulate the users's environment variables to run a choice of the needed programs and versions. The most important of these variables are ''$PATH'', telling the system where to find executable files such as ''matlab'' or ''mpirun'', and ''$LD_LIBRARY_PATH'', telling the system where to find shared libraries that an executable calls and requires. You can manipulate the environment variables yourself instead of calling modules, but generally there is no advantage in doing so.
The four critical module commands are ''list'' (currently loaded),''avail'' (all available), ''load'', and ''purge''. The combination purge/load clears all loaded modules and sets new ones:
$ module list
Currently Loaded Modulefiles:
1) intel/14.0.3 2) impi/5.0.0
$ module avail
-------- /share/apps/modules/Modules/3.2.10/modulefiles ------------------------------------------------
dot gcc/4.9.1 impi/5.1.1 mkl/14.0.3 module-info mvapich2/2.1 openmpi/1.8.6 perl/5
gcc/4.7.2 impi/5.0.0 intel/14.0.3 module-git modules null openmpi/1.8.8 use.own
$ module purge
$ module load intel/14.0.3 impi/5.1.1
$ module list
Currently Loaded Modulefiles:
1) intel/14.0.3 2) impi/5.1.1
$ module purge
$ module load intel/14.0.3 mkl/14.0.3 mvapich2/2.1
$ module list
Currently Loaded Modulefiles:
1) intel/14.0.3 2) mkl/14.0.3. 2) mvapich2/2.1
''module avail'' can be slow to load. A quicker way to see the top-level names only is (on any cluster, this is razor)
$ ls /share/apps/modulefiles
abinit cdhit flash idb mkl netcdf pindel reapr tophat
abyss changa gadget ifort module-cvs null platform_mpi samtools transdecoder
allpaths cmake gamess impi module-info nwchem pqs scipy trilinos
augustus cplex gcc infernal modules open64 proj.4 sickle trinity
bbmap crb-blast gdal intel mono opencv python siesta usearch
bib cuda GenomeVISTA java moose openfoam qiime soapdenovo2 use.own
blast cufflinks glpk last mothur openmpi qlogicmpi spades velvet
blat dDocent gotoblas2 LIGGGHTS mpiblast orca qmcpack sra-tools ViennaRNA
boost deepTools grass maker mpt os quast sunstudio visit
bowtie dot gromacs matlab muscle parallel R swat wise2
bowtie2 emboss gurobi mcl mvapich pear randfold swig
busco fastqc hdf5 migrate-n mvapich2 perl raxml symphony
bwa fftw hmmer miRDeep ncl PGI rDock tcltk
''ls -R /share/apps/modulefiles | more'' gives a full list of every file.
==.bashrc==
A script file in each user's home directory called ''.bashrc'' also sets environment variables such as ''$PATH'' and ''$LD_LIBRARY_PATH'' at each login. Since the file name begins with a period, the file is "hidden" so it does not register by ''ls'' but does register by ''ls -a''.
If you use a different shell than ''bash'' such as ''tcsh'', there will be an analogous file such as ''.cshrc'' which does the same functions in ''csh'' syntax.
The default .bashrc loaded with a new account includes three ''module'' loads. You can and usually should edit this file to get the effect you want.
$ cat ~/.bashrc
. /etc/profile.d/env-modules.sh
ulimit -s unlimited 2>/dev/null
ulimit -l unlimited 2>/dev/null
#if using goto/mkl blas with mpi these should be set to 1 unless you want hybrid mpi/openmp
export GOTO_NUM_THREADS=1
export OMP_NUM_THREADS=1
export MKL_NUM_THREADS=1
#enter your modules here
module load intel
module load openmpi
module load mkl
[ -z "$PS1" ] && return
PS1='`/bin/hostname -s`:`whoami`:`echo $PWD | sed "s=$HOME=="`$ '
alias ls='ls --color=auto'
module list
''.bashrc'' is sourced at the beginning of each interactive job. There is a similar file ''.bash_profile'' sourced at the beginning of each non-interactive job. In our setup, we source ''.bashrc'' from ''.bash_profile'' so that the files are effectively the same, thus reducing the maintenance effort, but you can separate them if necessary. Interactive or batch is determined in ''.bashrc'' by ''[ -z "$PS1" ] && return'' which drops out of the loop on batch runs, so commands following that are for interactive sessions only, like setting the value of the prompt ''$PS1''. Commands towards the top of ``.bashrc`` are for both interactive and batch. You can add commands to ''.bash_profile'' for batch jobs only.
For csh-users, module commands should operate identically under ''tcsh'' but they are generally untested.
On multiple-node parallel jobs, ''.bashrc'' can do some unexpected things as the system spawns a shell on each node. Here are some recommended module/.bashrc setups for different cases:
** You run only one program, or all the programs you run use the same modules, or each uses different modules that don't conflict **
Put the ''module load ...'' in ''.bashrc'', above ''[ -z...''. The same environment will be loaded from ''.bashrc'' for every interactive session, batch job, and MPI program if any. Many modules, for instance ''R'' and ''matlab'' and ''python'', can be assumed to not conflict, though most of the very many combinations have not been tested. Modules that definitely do conflict are MPI modules, only one may be safely used at a time, and multiple versions of the same program, like ''gcc/4.7.1'' and ''gcc/4.9.1''. Multiple compilers, such as ''gcc'' and ''intel'' usually don't conflict, but for MVAPICH2 and OpenMPI, the compiler module is used to load the MPI module, so multiple compiler modules should be loaded in order (1) compiler module you want to use with MPI (2) MPI module (3) additional compiler module. In some cases, gnu MPI programs using MKL libraries can want a library only available from the Intel compiler, so a combination like ''module load gcc/4.7.2 mkl/14.0.3 openmpi/1.8.8;module load intel/14.0.3'' may be necessary. The last ''intel/14.0.3'' may show a harmless warning message.
** You use different (conflicting) modules for different programs, but only run single-node batch jobs **
If you put ''module load ...'' in your ''.bashrc'', every interactive session and batch and MPI thread will load that, which won't be good if it's a slave compute nodes loading the wrong MPI version. Delete or comment out (add leading "#" to) the ''module load ...'' in ''.bashrc''. Put the relevant ''module load ...'' in your batch scripts after the ''#PBS'' statements, for example:
#PBS ...
#PBS -l node=1:ppn=12
module purge
module load R openmpi
cd $PBS_O_WORKDIR
R < myprog.R --nosave --vanilla
In this case, for interactive sessions such as compiling, type the relevant ''module load ...'' in your session before work.
** You use different (conflicting) modules for different programs, and also run multi-node MPI jobs **
This is a more difficult case. The first two solutions won't always work. If a module is set in a batch script using multiple nodes, the module definitely applies to the MPI processes running in the first or "master" compute node (usually the first and lowest numbered assigned node in our batch configuration) but does not necessarily apply to the "slave" compute nodes, depending how different MPI types issue remote threads. Multiple nodes imply MPI is being used, and the solution varies by MPI type. A certain form of the ''mpirun'' statement for each MPI type is required. See the [[MPI|MPI]] article for more details.