Finding the Strongly Connected Components of a directed graph in a shared memory multiprocessor

Assignment for 2022-2023 Parallel and Distributed Systems course, Aristotle University of Thessaloniki

A strongly connected component (SCC) is a maximal subgraph of a directed graph in which there is a path from each vertex to any other vertex in the subgraph.

In this assignment, I'm implementing a parallel algorithm to identify the number of SCCs in large directed graphs, using OpenCilk, OpenMP and PThreads.

Dependencies:

• gcc/g++ compiler
• make for building using Makefile
• OpenCilk installation (default directory for the OpenCilk compiler is /opt/opencilk/bin/clang++ , modify the first line of the Makefile if somewhere different).

How to build:

• Navigate to the directory of the Makefile and run make command. Executables should be created in folder ./exec/ .

How to run:

• Obtain .mtx files that represent graphs.
• For any of the executables that were created, run ./exec/some_exe my_graph.mtx (an additional number may be passed to indicate running the benchmark for more iterations, e.g. exec/pthreads celegansneural.mtx 500)