parallel-computing-lab

Parallel computing course lab project code.

Python Code

• analysis.ipynb Jupyter notebook for the analysis and plotting of the results.
• convert.py Helper script to convert .tif images into .rgb files containing raw pixel information.
• exec.py Helper script to create mpirun commands using metadata of the images to run the C program.
• metadata.py Helper script to extract metadata from image files (name and resolution).

Requirements

Scripts convert.py and metadata.py require the Pillow library to run. Conversion script expects input images in ./img_tif/ and will output .rgb images in ./img_rgb/.

Usage

# Pre-Req: Download .tif images in ./img_tif/
python3 convert.py
# Generate metadata
python3 metadata.py
# Generation execution commands
python3 exec.py

C Code

• pixelate.c Main program that implements the MPI algorithm.
• pix_kernel.c / pix_kernel.h Source files for the pixelate kernel implementation.

Requirements

The MPI algorithm requires a working OpenMPI installation to build and run and a compatible C compiler.

Usage

Compile with: mpicc -o pixelate pixelate.c pix_kernel.c

Run algorithm on the heic0601a Hubble Orion Nebula image, converted from tif to rgb using convert.py. The algorithm is run using 32 processors and a kernel window of 32x32px:

mpirun -np 32 ./pixelate img_rgb/heic0601a.rgb 18000 18000 3 32 32

Example job32.slurm file:

#!/bin/bash
#SBATCH -J pixelate32
#SBATCH -o output_%j.txt
#SBATCH -e errors_%j.txt
#SBATCH --mail-user <email>
#SBATCH --mail-type all
#SBATCH -t 00:10:00
#SBATCH -n 32
#SBATCH -p allgroups
#SBATCH --mem 8G

cd $SLURM_SUBMIT_DIR

mpicc -o pixelate pixelate.c pix_kernel.c
echo "Run 1"
mpirun -np $SLURM_NTASKS ./pixelate img_rgb/heic0601a.rgb 18000 18000 3 32 32
echo "Run 2"
mpirun -np $SLURM_NTASKS ./pixelate img_rgb/heic0601a.rgb 18000 18000 3 32 32
echo "Run 3"
mpirun -np $SLURM_NTASKS ./pixelate img_rgb/heic0601a.rgb 18000 18000 3 32 32
echo "Run 4"
mpirun -np $SLURM_NTASKS ./pixelate img_rgb/heic0601a.rgb 18000 18000 3 32 32
echo "Run 5"
mpirun -np $SLURM_NTASKS ./pixelate img_rgb/heic0601a.rgb 18000 18000 3 32 32

Submit using sbatch job32.slurm