Open your project properties, and go to Configuration Properties->Debugging

All we have to do is to fill 3 textboxes:

1. MPIRun Command is the path + filename of your mpirun applcation(usually mpiexec.exe or mpirun.exe), In my case it is "c:\Program Files\MPICH2\bin\mpiexec.exe" (do not forget the “”).
2. MPIRun Arguments are the arguments we want to pass to the mPIRun command, at very least we have to tell mpi the number processes to spawn, so we use –n 2 for 2 processes (change 2 as you wish).
3. MPIShim Loacation is the path + filename of your mpishim.exe file. Mpishim.exe is diffrent for every release of visual studio and platform you have. For example its location for Visual Studio 2005 for 32bit platforms should be “C:\Program Files\Microsoft Visual Studio 8\Common7\IDE\Remote Debugger\x86”

• Optimum Design of High-Rise Steel Buildings using an Evolution Strategy Integrated Parallel Algorithm
• delphi and mpi, closer look 2
• DELPHI and MPI, closer look 1
• A Comparative Study on Two Different Direct Parallel Solution Strategies for Large-Scale Problems
• send std::string with mpi
• Delphi and mpi in 4 steps
• Installing boost for visual studio

The second part is about calling MPI functions from Delphi.

Name Convention

No change here. Since we are using a direct translation of the original MPI header, all the original names are there.

Sending, Receiving Data

No surprise here too, here are some pointers:

Variables

Since MPI needs pointers to variables, use @ operator to get the pointer to your variables.

MPI_Comm_rank(MPI_COMM_WORLD,@myid);

For getting the size of variables use the sizeoff function.

Arrays

Again we need the starting address of the arrays.

Lets say we have an array named as “sizeArray”

For dynamic arrays use @(sizeArray[0])

For static arrays use  @(sizeArray[1]) //  assuming the array starts from 1

Strings

Since no one knows the memory map of a Delphi string you cannot use them with MPI. You have to go with short strings.

Debugging

Bad news here, Delphi has no support for parallel debugging. You have to go with displaying data to screen, or using a log file.

I was going to write a 3rd article about creating parallel applications with GUI, but since it is a general subject I decided to write the article separately, so this series and here.

• Delphi and mpi in 4 steps
• Optimum Design of High-Rise Steel Buildings using an Evolution Strategy Integrated Parallel Algorithm
• DELPHI and MPI, closer look 1
• send std::string with mpi
• MPI Debugging with Visual Studio
• A Comparative Study on Two Different Direct Parallel Solution Strategies for Large-Scale Problems
• pugg
• Installing boost for visual studio
• what i need from delphi 2010

In this first part I will take a closer look at the installation process.

1. Install an MPI library

MPI itself is not a library but an interface. So you have to find an implementation suiting your needs. MPICH2 is a long time favorite of mine, as it is free, well developed and documented.

All you have to do download and install the library on every computer of your cluster.

2.Get a Binding

Unfortunately, MPICH2 does not include bindings for Delphi. Fortunately Lazarus people created a pascal file  from the c include files that we can use.

You can find the slightly changed version of this file here Delphi mpi bindings (65).  All you need to do is download the file and insert it into your project. Since the dll files from MPICH2 will be in a path where Windows can find no other action is necessary.

3.Code!

Add uses MPI; to your code, that’s it. Here is a small example:

program MPIExample;
uses  MPI;

var myid: integer;
begin
  MPI_Init(nil,nil);
  MPI_Comm_rank(MPI_COMM_WORLD,@myid);
  writeln('id=',myid);
  MPI_Finalize;

end.

• Delphi and mpi in 4 steps
• Optimum Design of High-Rise Steel Buildings using an Evolution Strategy Integrated Parallel Algorithm
• delphi and mpi, closer look 2
• MPI Debugging with Visual Studio
• A Comparative Study on Two Different Direct Parallel Solution Strategies for Large-Scale Problems
• send std::string with mpi
• what i need from delphi 2010

A Comparative Study on Two Different Direct Parallel Solution Strategies for Large-Scale Problems

T. Bahcecioglu, S. Ozmen and O. Kurc

This paper was presented in PARENG2009 Pecs, Hungary.
doi:10.4203/ccp.90.40
Web Page

• Optimum Design of High-Rise Steel Buildings using an Evolution Strategy Integrated Parallel Algorithm
• MPI Debugging with Visual Studio
• delphi and mpi, closer look 2
• DELPHI and MPI, closer look 1
• send std::string with mpi
• Delphi and mpi in 4 steps

string s = "before";
int size = 0;
if (myRank == 0)
{
   s = "after";
   size = s.size();
}
BroadCast(&size,1);
if (myRank != 0) s.resize(size);
BroadCast(s.data(),size);

• delphi and mpi, closer look 2
• Delphi and mpi in 4 steps
• Optimum Design of High-Rise Steel Buildings using an Evolution Strategy Integrated Parallel Algorithm
• MPI Debugging with Visual Studio
• DELPHI and MPI, closer look 1
• pugg
• Installing boost for visual studio
• A Comparative Study on Two Different Direct Parallel Solution Strategies for Large-Scale Problems

program HelloWorld1;

uses  MPI;

var myid: integer;
begin
MPI_Init(nil,nil);
MPI_Comm_rank(MPI_COMM_WORLD,@myid);
writeln('id=',myid);
MPI_Finalize;

end.

• DELPHI and MPI, closer look 1
• delphi and mpi, closer look 2
• Optimum Design of High-Rise Steel Buildings using an Evolution Strategy Integrated Parallel Algorithm
• send std::string with mpi
• MPI Debugging with Visual Studio
• A Comparative Study on Two Different Direct Parallel Solution Strategies for Large-Scale Problems
• pugg
• Installing boost for visual studio
• what i need from delphi 2010