1. ERGoUrHIP Workshop, 2006.03.09 - 15 Progress Report on Parallel Processing with Flower Marek Szuba Heavy-Ion Reactions Group Warsaw University of Technology

2. ERGoUrHIP Workshop, 2006.03.09 - 15 Short Reminder: The Idea We were looking for a parallel computation approach that would be: ● simple to implement and use ● low-overhead ● scalable ● modular and numerics-independent ● portable

3. ERGoUrHIP Workshop, 2006.03.09 - 15 ● Based on PVM, an established and reliable solution ● Automatically selects best means of inter-process communication ● Time-synchronised using data itself, not separately ● Only one function modified in original code Short Reminder: Features

4. ERGoUrHIP Workshop, 2006.03.09 - 15

5. Modus Operandi 1)Divide space into equal sections 2)Initialise bees with section data 3)Transmit initial conditions 4)Processing loop: a)transmit boundary data b)receive and assemble post-step values

6. ERGoUrHIP Workshop, 2006.03.09 - 15 Previously... Results obtained in July 2005: ● Not good at all... ●...however, data transmission proven correct! ● no solution found at the time Results obtained in July 2005: ● Not good at all... ●...however, data transmission proven correct! ● no solution found at the time

7. ERGoUrHIP Workshop, 2006.03.09 - 15...and Now SerialPVM, 8 machines

8. ERGoUrHIP Workshop, 2006.03.09 - 15 Accuracy Let us compare PVM and serial results for energy density plots from previous slide:

9. ERGoUrHIP Workshop, 2006.03.09 - 15 Time Benefits Test platform: Athlon 64 3000, 1.5 GB RAM Network: Fast Ethernet Z Grid: 100x100x100 Time steps: 100 Algorithm: MustaFORCE Network overhead: 4.55% more time 15.2% of serial time! 15.2% of serial time! Preliminary: significant further improvement with Gigabit Ethernet

10. ERGoUrHIP Workshop, 2006.03.09 - 15 Exploiting Open Architecture Modular architecture of Flower allows us to use various integrating techniques – but at the same time is suitable for almost any kind of calculations. This is of course also possible with PVM. Take Conway's game of life, for instance: http://en.wikipedia.org/wiki/Conway's_Game_of_Life

11. ERGoUrHIP Workshop, 2006.03.09 - 15 Game of Life

12. ERGoUrHIP Workshop, 2006.03.09 - 15 Summary 1.PVM module for Flower is now COMPLETE 2.Highly effective scaling 3.No inaccuracies comparing to serial code 4.Modular architecture allows re-usability other integrating functions......but also completely different simulations What now: How about MPIFlower?