PyCOMPSs Matrix Multiplication, out-of-core, using files
Version 1

Workflow Type: COMPSs

Name: Matrix multiplication with Files
Contact Person:
Access Level: public
License Agreement: Apache2
Platform: COMPSs


Matrix multiplication is a binary operation that takes a pair of matrices and produces another matrix.

If A is an n×m matrix and B is an m×p matrix, the result AB of their multiplication is an n×p matrix defined only if the number of columns m in A is equal to the number of rows m in B. When multiplying A and B, the elements of the rows in A are multiplied with corresponding columns in B.

In this implementation, A and B are square matrices (same number of rows and columns), and so it is the result matrix C. Each matrix is divided in N blocks of M doubles. The multiplication of two blocks is done by a multiply task method with a simple three-nested-loop implementation. When executed with COMPSs, the main program generates N^3^ tasks arranged as N^2^ chains of N tasks in the dependency graph.

Execution instructions


runcompss --lang=python src/ numberOfBlocks blockSize


  • numberOfBlocks: Number of blocks inside each matrix
  • blockSize: Size of each block

Execution Examples

runcompss --lang=python src/ 4 4
runcompss src/ 4 4
python -m pycompss src/ 4 4


No build is required

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Version History

Version 1 (earliest) Created 30th May 2023 at 09:55 by Raül Sirvent

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The Workflows and Distributed Computing Team (

Sirvent, R. (2023). PyCOMPSs Matrix Multiplication, out-of-core, using files. WorkflowHub.

Views: 865

Created: 30th May 2023 at 09:55

Last updated: 26th Oct 2023 at 10:42

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Total size: 4.26 MB
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