Quantum ESPRESSO: Difference between revisions
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The above example requests two whole nodes for a total of 64 single-threaded processes. This is certainly more processors than is needed for the silicon tutorial case. Please be aware that suitable selection of a process count is complicated, but it is your responsibility to choose an efficient number. | The above example requests two whole nodes for a total of 64 single-threaded processes. This is certainly more processors than is needed for the silicon tutorial case. Please be aware that suitable selection of a process count is complicated, but it is your responsibility to choose an efficient number. | ||
= Segfaults with OpenMPI 3.1.2 = | |||
Users have reported random segfaults on Cedar when using Quantum ESPRESSO versions compiled for OpenMPI 3.1.2 in single-node jobs (shared memory communication). These issues seem not to happen with other versions of OpenMPI. If you experience such problems, first try to use an OpenMPI 2.1.1-based toolchain. For example: | |||
{{Commands | |||
|module load gcc/5.4.0 | |||
|module load openmpi/2.1.1 | |||
|module load quantumespresso/6.3 | |||
}} | |||
= Notes = <!--T:5--> | = Notes = <!--T:5--> | ||
Revision as of 21:38, 20 January 2020
- "Quantum ESPRESSO is an integrated suite of Open-Source computer codes for electronic-structure calculations and materials modeling at the nanoscale. It is based on density-functional theory, plane waves, and pseudopotentials.
- [...]
- Quantum ESPRESSO has evolved into a distribution of independent and inter-operable codes in the spirit of an open-source project. The Quantum ESPRESSO distribution consists of a “historical” core set of components, and a set of plug-ins that perform more advanced tasks, plus a number of third-party packages designed to be inter-operable with the core components.[1]
Usage[edit]
To use Quantum ESPRESSO, you need to load a module (see Using modules). You can see available versions using module avail quantumespresso or module spider quantumespresso, and load one with (for example), module load quantumespresso/6.1.
#!/bin/bash
#SBATCH --account=def-someuser
#SBATCH --time=0-1:00 # DD-HH:MM
#SBATCH --nodes=2
#SBATCH --tasks-per-node=32 # MPI tasks
#SBATCH --mem=0 # all memory on node
module load quantumespresso/6.1
export OMP_NUM_THREADS=1
srun pw.x < si.scf.in
The above example requests two whole nodes for a total of 64 single-threaded processes. This is certainly more processors than is needed for the silicon tutorial case. Please be aware that suitable selection of a process count is complicated, but it is your responsibility to choose an efficient number.
Segfaults with OpenMPI 3.1.2[edit]
Users have reported random segfaults on Cedar when using Quantum ESPRESSO versions compiled for OpenMPI 3.1.2 in single-node jobs (shared memory communication). These issues seem not to happen with other versions of OpenMPI. If you experience such problems, first try to use an OpenMPI 2.1.1-based toolchain. For example:
[name@server ~]$ module load gcc/5.4.0
[name@server ~]$ module load openmpi/2.1.1
[name@server ~]$ module load quantumespresso/6.3
Notes[edit]
- Pseudopotentials
- There is not currently a system-wide repository of pseudopotentials for Quantum ESPRESSO within Compute Canada. You must find or create and store your own pseudopotential files.