Grid Communication Simulator

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Grid Communication Simulator

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

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Grid Programming Models

• There has been significant development of
  parallel programming models
• They cannot be applied directly to the Grid
  Infrastructure
• MPI
• Java RMI
• Corba

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MPI on the Grid

• MPI Message Passing Interface
• MPICH Well known MPI implementation
• MPICH-G2 Globus device implemented

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MPICH-G2
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Performance Consideration

• Usage of TCP/IP as main transport protocol
  introduces lower performance
• Wide Area Network performance compared to
  specialized Cluster Network performance
• hence
• Trying to increase the overall performance

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Performance Techniques

• MPICH-G2 over vendor MPI
• Better communication patterns
• Topology aware collective communications
• Broadcast
• Gather/Scatter
• Barrier
• Reduce

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Example

• Binomial Tree
• Optimal broadcast algorithm

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Example

• Topology Unaware Solution

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Example

• Topology Aware Solution

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Grid Communication Simulator

• Implemented using Java 1.4
• Purpose
• Visual representation of communication patterns
• Has implemented collective communications
• In development

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Grid Communication Simulator

• The programs executed on the virtual processors
  are Java programs
• Example

import java.util. import edu.ii.grid.simulator.
public class FlatTreeBroadcast extends
edu.ii.grid.simulator.Program public void
run() if (processor.getID() 0) for
(int i 1 i lt Processor.getCount() i)
Integer data new Integer(1)
processor.send( new Packet( data, new
GRIDAddress(i) ) ) else
Packet p null p processor.recieve()

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Grid Communication Simulator

• Grid simulator main window

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Grid Communication Simulator

• Grid simulator usage

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Grid Communication Simulator
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Grid Communication Simulator

• for (int i 0 i lt matriceA.length i)
• for (int j 0 j lt matriceAi.length j)
• matriceAij new Integer((int)(Math.random
  ()100))
• row CollectiveCommunication.flatTreeScatter(proc
  essor, matriceA)

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Grid Communication Simulator