ICPP 2009 in Vienna

I presented our initial work on Offloading Collective Operations, which is the definition of an Assembly language for group operations (GOAL), at ICPP’09 in Vienna. I was rather disappointed by this year’s ICPP. We had some problems with the program selection already before the conference (I’ll happily tell you details on request) and the final program was not great. Some talks were very entertaining though. I really enjoyed the P2S2 workshop, especially Pete Beckman’s keynote. Other highlights (in my opinion) include:

  • Mondrian’s “A resource optimized remote-memory-access architecture for low-latency communication” (I need to talk to those guys (I did ;))
  • Argonne’s “Improving Resource Availability By Relaxing Network Allocation Constraints on the Blue Gene/P” (I need to read the paper because I missed the talk due to chaotic re-scheduling, but Narayan’s 5-minute elevator pitch summary seemed very interesting)
  • Prof. Resch’s keynote on “Simulation Performance through Parallelism -Challenges and Options” (he even mentioned the German Pirate party which I really enjoyed!)
  • Brice work with Argonne on “Cache-Efficient, Intranode Large-Message MPI Communication with MPICH2-Nemesis”
  • Argonne’s “End-to-End Study of Parallel Volume Rendering on the IBM Blue Gene/P” (yes, another excellent Argonne talk right before my presentation :))

Here are some nice pictures:
My talk at the last day was a real success (very well attended, even though it was the last talk in the conference)! It’s good to have friends (and a good talk from Argonne right before mine :-)). Btw. two of the three talks in the (only) “Information Retrieval” session were completely misplaced and had nothing to do with it, weird …

My co-author, friendly driver, and camera-man and me in front of the parliament.

EuroPVM/MPI 2009 report

This year’s EuroPVM/MPI was held in Helsinki (not quite, but close to it). I stayed in Hanasaari, a beautiful island with a small hotel and conference center on it. It’s a bit remote but nicely surrounded by nature.

The conference was nice, I learned about formal verification of MPI programs in the first day’s tutorial. This technique seems really nice for non-deterministic MPI programs (how many are there?) but there are certainly some open problems (similar to the state explosion of thread-checkers). The remainder of the conference was very nice and it feels good to meet the usual MPI suspects again. Some highlights were in my opinion:

  • Edgar’s “VolpexMPI: an MPI Library for Execution of Parallel Applications on Volatile Nodes” (indeterminism is an interesting discussion in this context)
  • Rusty’s keynote on “Using MPI to Implement Scalable Libraries” (which I suspect could use collectives)
  • Argonne’s “Processing MPI Datatypes Outside MPI” (could be very very useful for LibNBC)
  • and Steven’s invited talk on “Formal Verification for Scientific Computing: Trends and Progress” (an excellent overview for our comunity)

The whole crowd:

Unfortunately, I had to leave before the MPI Forum information session to catch my flight.
Videos of many talks are available at Videos. All-in-all, it was worth to attend. Next year’s EuroMPI (yes, the conference was finally renamed after the second year in a row without a PVM paper) will be in Stuttgart. So stay tuned and submit papers!

MPI 2.2 is now officially ratified by the MPI Forum!

I just came back from lunch after the MPI Forum meeting in Helsinki. This meeting focused again (the last time) on MPI 2.2. We finished the review of the final document and edited several minor things. Bill did a great job in chairing and pushing the MPI 2.2 work and the overall editing. Unfortunately, we did not meet our own deadlines, i.e., the chapters and reviews were not finished two weeks ago (I tried to push my chapters (5 and 7) as hard as possible, but getting the necessary reviews was certainly not easy). However, the whole document was reviewed (read) by forum members during the meeting and my confidence is high that everybody did a good job.

Here are the results of the official vote on the main document:
yes: 14
no: 1
abstain: 2 (did not participate)

The votes by chapter will be online soon.

The feature-set of the standard did not change. I posted it earlier here and Jeff also. But it’s official now! Implementors should now get everything implemented so that all users can enjoy the new features.

Here is a local copy (mirror) of the official document: mpi-report-2_2.pdf (the creation date might change)

One downside is that we already have errata items for things that were discovered too late in the process. This seems odd, however, we decided that we should not break our own rules. And even if the standard says that an MPI_BOOL is 4 bytes, we had to close the door for changes at some point. The errata (MPI_BOOL is one byte) will be voted on and posted soon on the main webpage.

Rolf will publish the MPI 2.2 book (like he did for MPI 2.1) and it will be available at Supercomputing 2009. I already ordered my copy :).

And now we’re moving on to MPI 3, so stay tuned (or participate in the forum)!