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The End of Grid Computing?

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In the year 2003 the MIT Technology review ranked "Grid Computing" among the 10 Emerging Technologies That Will Change the World [1]. We are now four years later and something is not going well with "Grid Computing". An indication that there is a problem can easily be seen by looking at the "Google Trends" plot for the term "Grid Computing": (click on the image to get the current trend). This finding can be compared with another buzz word, "Virtualization", which is older than "Grid Computing" and yet is gaining more and more momentum: There is however one exception. The Academic Grid is still having lot's of glory thanks to the huge heavily funded European (EGEE) and other US projects. When LHC data will start to be taken at CERN it will reach it's top importance. But, it seems that for other scientific projects Grid Computing is not going to be such a success. It will remain as "Nice to have" but will never...
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Parallel Debugging with a Serial Debugger

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Parallel Debuggers are important tools when trying to eliminate bugs in parallel programs. Commercial parallel debuggers are expensive. In this blog post I will show you a free and open source alternative which is good enough for education purposes and for small codes. Suppose you want to debug the famous cpi.c code which computes an approximation to pi by a parallel numerical integration. This demo uses the free Data Display Debugger (ddd) which is based on gdb but has a nice GUI. Step 1, compile: mpicc -g -o cpi ./cpi.c Step 2, run (without a debugger): mpirun -np 2 ./cpi Step 3, run with the free Data Display Debugger (ddd) : mpirun -np 2 ddd ./cpi The last command will open two MPI processes (instances) of ddd each running cpi, see screen capture: Finally, I enclose here a short video which I hope is convincing: hi-res version:  https://youtu.be/N_J4NKJkuMs Happy (Free) MPI debugging!
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MPI.NET Tutorial

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In this post I will show step by step how to install and execute MPI (Message Passing Interface) parallel programs in the .NET environment. A much more detailed tutorial is available here . 1) Installation: My computer is running Windows Vista and Visual Studio 2008 is already installed. Download and install the HPC Pack 2008 (next 5 figures): Then install the MPI.NET SDK.msi (see next 4 figures): 2) Test the installation from the command line (next 3 figures): A "Ping-Pong" program Serial run: As should be, the firewall detects the communication traffic and the user should allow it: Parallel run: 3) MPI "Hello" demo using Visual Studio 2008 and C# (next 5 figures): Start a new console C# project: Add Reference to the MPI component: Build the executable: Execute the parallel program with 8 threads: Verifying the execution of the 8 threads by looking at the Task Manager: That's all for now. Your comments are welcome. Guy Tel-Zur Email: tel-zur@computer.org
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