Theta-ALCF (XC40)¶

Theta is a Cray XC40 located at Argonne National Laboratory, maintained by ALCF.

$ ssh <username>@theta.alcf.anl.gov

Building WEST¶

Important: The ELPA eigensolver library is found to greatly improve the performance of Quantum ESPRESSO on Theta. ELPA can be installed following these steps (tested on July 22, 2022):

$ cat build_west.sh
#!/bin/bash

module unload cray-libsci
module load cray-python/3.8.2.1

export CRAYPE_LINK_TYPE=dynamic
export LD_LIBRARY_PATH=$MKLROOT/lib/intel64:$LD_LIBRARY_PATH
export LD_LIBRARY_PATH=/opt/intel/compilers_and_libraries_2020.0.166/linux/compiler/lib/intel64:$LD_LIBRARY_PATH
export FC=ftn
export CC=cc
export CXX=CC

wget https://elpa.mpcdf.mpg.de/software/tarball-archive/Releases/2021.11.002/elpa-2021.11.002.tar.gz
tar zxf elpa-2021.11.002.tar.gz
cd elpa-2021.11.002

# Manually edit configure: comment out lines 4474 through 4496, otherwise configure would fail due to cross compilation

mkdir build
cd build

../configure --prefix=$(pwd) LDFLAGS="$MKLROOT/lib/intel64/libmkl_scalapack_lp64.so -Wl,--start-group $MKLROOT/lib/intel64/libmkl_intel_lp64.so $MKLROOT/lib/intel64/libmkl_sequential.so $MKLROOT/lib/intel64/libmkl_core.so $MKLROOT/lib/intel64/libmkl_blacs_intelmpi_lp64.so -Wl,--end-group" --disable-sse-assembly --disable-sse --disable-avx512 --enable-c-tests=no

make -j 8
make install

WEST executables can be compiled using the following script (tested on July 22, 2022):

$ cat build_west.sh
#!/bin/bash

module unload cray-libsci
module load cray-python/3.8.2.1

export CRAYPE_LINK_TYPE=dynamic
export LD_LIBRARY_PATH=$MKLROOT/lib/intel64:$LD_LIBRARY_PATH
export LD_LIBRARY_PATH=/opt/intel/compilers_and_libraries_2020.0.166/linux/compiler/lib/intel64:$LD_LIBRARY_PATH
export LD_LIBRARY_PATH=/opt/python/3.8.2.1/lib:$LD_LIBRARY_PATH
export MPIF90=ftn
export F90=ftn
export CC=cc
export SCALAPACK_LIBS="$MKLROOT/lib/intel64/libmkl_scalapack_lp64.so -Wl,--start-group $MKLROOT/lib/intel64/libmkl_intel_lp64.so $MKLROOT/lib/intel64/libmkl_intel_thread.so $MKLROOT/lib/intel64/libmkl_core.so $MKLROOT/lib/intel64/libmkl_blacs_intelmpi_lp64.so -Wl,--end-group"

# Edit ELPA installation path
./configure --enable-openmp --with-scalapack=intel --with-elpa-include=/path/to/elpa-2021.11.002/build/include/elpa-2021.11.002/modules --with-elpa-lib=/path/to/elpa-2021.11.002/build/lib/libelpa.a

make -j 8 pw

cd West

make conf PYT=python3 PYT_LDFLAGS="`python3-config --ldflags --embed`"
make -j 8 all

To use the script do:

$ bash build_west.sh

Running WEST Jobs¶

The following is an example executable script run_west.sh to run the wstat.x WEST executable on two nodes of Theta with 64 MPI ranks per node. The <project_name> must be replaced with an active project allocation.

Important: The following environment variable is needed to work around a bug in ROMIO, Cray MPICH.

export ROMIO_FSTYPE_FORCE="ufs:"

$ cat run_west.sh
#!/bin/bash
#COBALT -n 2
#COBALT -t 00:20:00
#COBALT -q debug-cache-quad
#COBALT -A <project_name>
#COBALT -O WEST

MPIRANKS_PERNODE=64
MPIRANKS=$((COBALT_PARTSIZE * MPIRANKS_PERNODE))
NTHREADS=1
HT=1

module unload cray-libsci
module load cray-python/3.8.2.1

export LD_LIBRARY_PATH=$MKLROOT/lib/intel64:$LD_LIBRARY_PATH
export LD_LIBRARY_PATH=/opt/intel/compilers_and_libraries_2020.0.166/linux/compiler/lib/intel64:$LD_LIBRARY_PATH
export LD_LIBRARY_PATH=/opt/python/3.8.2.1/lib:$LD_LIBRARY_PATH

export ROMIO_FSTYPE_FORCE="ufs:"

echo "Running Cobalt Job $COBALT_JOBID."

export OMP_NUM_THREADS=$NTHREADS
aprun -n $MPIRANKS -N $MPIRANKS_PERNODE -cc depth -d $NTHREADS -j $HT ./wstat.x -i wstat.in &> wstat.out

Make the script executable:

$ chmod 755 run_west.sh

Job submission is done with the following:

$ qsub run_west.sh