#!/bin/bash #SBATCH --job-name=G16_HF #SBATCH --nodes=1 #SBATCH --ntasks-per-node=16 #SBATCH --mem=64G #SBATCH --time=24:00:00 export GAUSS_SCRDIR=/local/scratch/$SLURM_JOB_ID mkdir -p $GAUSS_SCRDIR Run Gaussian with OpenMPI hybrid g16 < input.com > output.log Clean up rm -rf $GAUSS_SCRDIR Benchmarks: Tuning Gaussian 16 on Linux Raw installation is not enough. You must optimize for your hardware. Memory Tuning In your input file, do not allocate all RAM ( %Mem=64GB ) if you run parallel jobs. The rule of thumb: %Mem = (Total RAM / Number of cores) * 0.8 (leave 20% for OS overhead). Linux Kernel Parameters For heavy DFT calculations (e.g., B3LYP/def2-TZVPP on 100 atoms), tune the swappiness and I/O scheduler:
g16 -p=8 test.com test.log Flag explanation: -p=8 uses 8 cores on the local machine. Most universities run Gaussian 16 Linux on SLURM clusters. Here is an optimal SLURM script: gaussian 16 linux
sudo mount -t tmpfs -o size=30G tmpfs /mnt/ramdisk export GAUSS_SCRDIR=/mnt/ramdisk Warning: Compute-intensive jobs like CCSD(T) can exceed this. Monitor df -h /mnt/ramdisk live. Even seasoned users encounter errors unique to the Gaussian 16 Linux ecosystem. 1. "Cannot open shared object file: libcuda.so.1" Cause: Gaussian tries GPU acceleration but CUDA is missing. Fix: Disable GPU in input: %GPUCPU=0 or use %NoGPU . 2. Segmentation Fault (core dumped) Cause: Stack limit too low on Linux. Fix: Run ulimit -s unlimited before launching Gaussian. Add to your .bashrc . 3. Linda Workers Keep Disconnecting Cause: Firewall blocks ports or SSH key authentication fails. Fix: Ensure passwordless SSH between nodes and open dynamic ports (e.g., 60000-61000) in iptables . Advanced Scripting: Automating Gaussian 16 on Linux Linux excels at batch processing. Here is a bash script to run a series of single-point energies on all .gjf files in a folder: The rule of thumb: %Mem = (Total RAM / Number of cores) * 0
sudo apt update && sudo apt install libc6 libstdc++6 libopenmpi-dev openmpi-bin For RHEL/Fedora: Here is an optimal SLURM script: sudo mount
sudo nano /etc/profile.d/gaussian.sh Add: