Grid Communication Simulator Boro Jakimovski Marjan Gusev Institute

Grid Communication Simulator Boro Jakimovski Marjan Gusev Institute of Informatics Faculty of Natural Sciences and Mathematics University of Sts. Cyril and Metodius Skopje, Macedonia

What is Grid? • Flexible, secure, coordinated resource sharing among dynamic collections of individuals, institutions, and resource From “The Anatomy of the Grid: Enabling Scalable Virtual Organizations” • Enable communities (“virtual organizations”) to share geographically distributed resources as they pursue common goals -- assuming the absence of… • • central location, central control, omniscience, existing trust relationships.

Performance Issues • Usage of TCP/IP as main transport protocol introduces lower performance • Wide Area Network performance compared to specialized Cluster Network performance • hence • The need for better performance

Collective Communications • MPICH-G 2 over vendor MPI • The advantage of Collective Communication – Topology aware collective communications • • • Broadcast Gather/Scatter Barrier Reduce …

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Grid Communication Simulator • Implemented using Java 1. 4 • Purpose – Visual representation of communication patterns – Has implemented collective communications – In development

Grid Communication Simulator • The programs executed on the virtual processors are Java programs – Example: import java. util. *; import edu. ii. grid. simulator. *; public class Flat. Tree. Broadcast extends edu. ii. grid. simulator. Program { public void run(){ if (processor. get. ID() == 0){ for (int i = 1; i < Processor. get. Count(); i++){ Integer[] data = {new Integer(1)}; processor. send( new Packet( data, new GRIDAddress(i) ) ); } } else { Packet p = null; p = processor. recieve(); } } }

Grid Communication Simulator • Grid simulator main window

Grid Communication Simulator • Grid simulator usage

Grid Communication Simulator

Grid Communication Simulator for (int i = 0; i < matrice. A. length; i++) for (int j = 0; j < matrice. A[i]. length; j++) matrice. A[i][j] = new Integer((int)(Math. random()*100)); row = Collective. Communication. flat. Tree. Scatter(processor, matrice. A);

Grid Communication Simulator