Category: Distributed Computing

Parallel and distributed computing

Review of Intel Parallel Advisor (part of Parallel Studio 2011)

November 30, 2010 Matt No Comments C++, Distributed Computing, Interactive RayTracer, Tools, Profiler

After my review of Intel Parallel Studio and then my post of Advisor Lite, I had the opportunity of doing the beta of Intel Advisor and then the final version of Parallel Studio.

The review will not be as thorough as the one on Advisor Lite, because Advisor is an update of Advisor Lite. It has some additional features, and that’s what I’d like to focus on.

I won’t dwell into the details of Intel’s new offer, suffice to say that Intel took the opportunity of changing some offers name and of incorporating some parts of Parallel Studio in its other products, and of course on Linux (which was left alone until then).

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Optimally use massively parallel clusters resources

June 15, 2010 Matt No Comments Distributed Computing, Tools, High Performance Computing

We have now several petaflopic clusters available in the Top500. Of course, we are trying to get the most of their peak computational power, but I think we should sometimes also look at optimal resource allocation.

I’ve been thinking about this for several months now, for work that has thousands of tasks, each task being massively data parallel. Traditionnally, one launches a job through one’s favorite batch scheduler (favorite or mandatory…) with fixed resources and during an estimated amount of time. This may work well in research, but in the industrial world, there often a new job that arises and that needs part of your scarce resources. You may have to stop your work, loose your current advances and/or restart the job with less resources. And then the cycle goes on.

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Book review: Programming Massively Parallel Processors: A Hands-on Approach

March 31, 2010 Matt 1 Comment Distributed Computing, Book review, Tools, High Performance Computing

Massively parallel processors are in the mood today. We had small parallel processors with a few cores and the ability to launch serevral threads on one core, we have now many cores on one processor and at the other end of the spectrum, we have GPUs. CPUs vendors are now going in this direction with Larabee and Fusion, and GPUs will still have more cores/threads/… It’s thus mandatory to understand this shift now.

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Thinking of good practices when developing with accelerators

January 5, 2010 Matt No Comments Tools, High Performance Computing, Design Patterns, C++, Development process, Distributed Computing

Due to the end of the free lunch, manufacturers started to provide differents processing units and developers started to go parallel. It’s kind of back to the future, as accelerators existed before today (the x87 FPU started as a coprocessor, for instance). If those accelerators were integrated into the CPU, their instruction set were also.

Today’s accelerators are not there yet. The tools are not ready yet (code translators) and usual programming practices may not be adequate. All the ecosystem will evolve, accelerators will change (GPUs are the main trend, but they will be different in a few years), so what you will do today needs to be shaped with these changes in mind. How is it possible to do so? Is it even possible?

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Review of Intel Parallel Studio

July 7, 2009 Matt 1 Comment Tools, Debugger, General, C++, Distributed Computing

I’ve played a little bit with Intel Parallel Studio. Let’s say it has been a pleasant trip out in the wildness of multithreaded applications.

Intel Parallel Studio is a set of tools geared toward multithreaded applications. It consists of three Visual Studio plugins (so you need a fully-fledged Visual Studio, not an Express edition):

  • Parallel Inspector for memory analysis
  • Parallel Amplifier for thread behavior and concurrency
  • Parallel Composer for parallel debugging

This is an update of the review I’ve done for the beta version. Since this first review, I’ve tried the official first version.

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Overview of TotalView, a parallel debugger

March 31, 2009 Matt 1 Comment C++, Distributed Computing, High Performance Computing, Debugger

Some months ago, I had a TotalView tutorial, thanks to my job. Now, I’ve actually used it to debug one of my parallel applications and I would like to share my experience with fantastic tool.
First TotalView is not only a parallel debugger available on several Linux and Unix platforms. It also is a memory checker (MemoryScape and the TotalView plugin) as well as a reverse debugger, that is, you can roll back the execution of a program, even after it crashed (where it would be useless with a standard debugger like GDB).

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Book review: Parallel Finite-Difference Time-Domain Method

February 3, 2009 Matt No Comments Distributed Computing, Book review

I came across the issue of how to teach a trainee how to write a parallel finite-difference time-domain (FDTD) method. There are a lot of books on the FDTD, but only a few on parallel ones. So I’ve decided to go for this book, knowing that some chapters won’t apply to our job (wave equations). My goal was to seek a book that would explain the basics of my issues.

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